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Compress PPT Files

Here you can compress PowerPoint PPT, PPTX, PPTM and ODG files online and reduce their file size of up to 90% the original size. Just select the PowerPoint file (max 50MB) to compress and wait.

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Both uploaded and compressed files are removed from our servers after approximately 6 hours.

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Compress PowerPoint files

Use our PowerPoint compressor to shrink the size of your PowerPoint file.

Compress PowerPoint files with 1 click​

Reduce the size of your PowerPoint files online with our FREE PowerPoint compressor. Easily compress PowerPoint files for email and more.

By using our compression tool you can reduce the size of your PowerPoint presentation by up to 90%. Try it now, it’s FREE.

Why our PowerPoint Compressor?

Our free PowerPoint compressor is super fast and has almost no limitations. Used another compression tool with success? Try our tool!

Compress PowerPoints quickly

We use the latest technology to compress your PowerPoint presentation. Want to email a presentation and it's too big? We got you covered. Simply upload your file and we will reduce the file size by up to 90%.

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Compress PPT Documents

Reduce and compress PowerPoint documents (.ppt, .pptx, .pptm, .odg) online to make them smaller, so you can better send them via email. You just need to select the PowerPoint file (~50MB) you want to compress.

Unlimited Compressions

You can use this service as much as you need, there is no limitation on daily usage.

From Any Web Browser

Works with all modern web browsers, such as Gogole Chrome, Microsoft Edge, Firefox, etc.

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All files are processed in the cloud, you do not need to install any software or plugin.

All Files Are Removed

Both uploaded and compressed documents are removed from our servers after a few hours.

Nothing to Configure

You just need to select the Office file you want to compress, there is nothing to configure.

Without Quality Loss

We use the best settings to maintain a good visual quality when compressing the file.

No Watermark

All compressed documents are free from watermarks, we do not add any logo on processed files.

101% Free to Use

Usage of this document compressor is totally free for both home and business users.

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Compress PPTX

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Why compress pptx files.

PPTX is a PowerPoint file type developed by Microsoft as part of Office 2007. PPTX was introduced by Microsoft in order to help users share information between programs more easily and to combat the increasingly large file sizes that they'd been in previous versions of Office. Not withstanding this change, file sizes of PPTX can still be exceedingly high especially if users have included images or video clips within the PPTX and those images/videos are themselves file types that are large in size. Given PPTX files can be so large it is perhaps no surprise that there is a need to compress them into more manageable file sizes. The compression works in a way that despite reducing the size of the file, there is no noticeable impact to the quality of the file. The advantage of compressing PPTX files is that they are more easily shared and can be downloaded that much quicker. Often, when shared, a large PPTX file can consume all of a recipient's mailbox which we all know can be so frustrating! By compressing the file that problem does not exist and all the while the same content can be sent to the recipient. The PPTX converter tool can be used today to compress those large PPTX files and make them smaller in size whilst retaining their quality. Compress your file today and you can share it safe in the knowledge you're not about to blow a users mailbox.

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We know how frustrating it is when something goes wrong and you can't reach out to someone for help, which is why we have a team in place to help you throughout the week.

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You can convert a file for free in just a few clicks, without any need to register for an account.

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Choose Files:

Compression settings:, output files:.

To compress all output files in a ZIP file, click " " icon on the right, then click "Add to ZIP". To download one single file, simply right-click on file link and click "Save link as...".

How to compress PPT files:

Set image quality first. Image quality value can be 1 (lowest image quality and highest compression) to 100 (best quality but least effective compression).

Drag multiple PowerPoint files to the "Choose Files" section. File extension name can be .ppt or .pptx. Each PowerPoint file size can be up to 40 MB.

Compress Files

The batch compression automatically starts when files are uploaded. Please be patient while files are uploading or compressing.

Output Files

The output files will be listed in the "Output Files" section. To compress all output files in a ZIP file, click " " icon on the right, then click "Add to ZIP". You can right-click on file name and click "Save link as..." to save the file. The output files will be automatically deleted on our server in two hours, so please download them to your computer or save them to online storage services such as Google Drive or Dropbox as soon as possible.

Unblock Files (if needed)

You may need to unblock the PowerPoint files if your Microsoft PowerPoint software can't open them. To unblock a file on Windows, right-click on the file and open "Properties". Under the General tab, towards the bottom you will see "Unblock" button or checkbox next to "Security: This file came from another computer and might be blocked to help protect this computer". Click on it, then click "Apply/OK".

The big change in PowerPoint 2007 was that the stable binary file format of 97-2003 (.ppt files) was replaced as the default by a new zipped XML-based Office Open XML format (.pptx files). Microsoft's explanation of the benefits of the change included: smaller file sizes, up to 75% smaller than comparable binary documents; security, through being able to identify and exclude executable macros and personal data; less chance to be corrupted than binary formats; and easier interoperability for exchanging data among Microsoft and other business applications, all while maintaining backward compatibility.

We can't find any open-source projects to compress PowerPoint presentations, therefore we wrote all the source codes from scratch by ourselves. This PowerPoint compressor compresses images in PowerPoint presentation to reduce file size.

Copyright © 2024 Compresss.com - A universal file compressor. All rights reserved. Privacy Policy Aconvert.com is a sister website of Compresss.com, it focuses on converting files instead of compressing files.

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Reduce the size of your PowerPoint files

How to compress powerpoint files, upload ppt or pptx.

First, you need to select an application from the available options and upload the PPT/PPTX file

Compress it

In the next step, you need to select the necessary settings and proceed to compress your image.

And finally, when everything is ready, you can download the file to your device and check it.

What is PowerPoint

PowerPoint is a program that is used to create presentations. It is included in Microsoft Office and is very popular these days. The application is relevant for business, advertising, teaching and lecture activities. It is actively used by schoolchildren and students. The program is great for public speaking and is an effective teaching tool. For many users, it has become an integral part of home and work computers. PowerPoint Presentation or Microsoft PowerPoint is a program for creating and delivering presentations. Here you can quickly and easily create bright, visual presentations decorated with pictures, tables, drawings, etc. It is used by teachers, students and schoolchildren with pleasure. After all, learning the program is not difficult, all you need is a little experience in Microsoft Word.

How PowerPoint compression works

PowerPoint is now a service that provides tremendous opportunities for creating and viewing slideshow-style presentations. It works with Microsoft Windows, macOS, Android and IOS operating systems. PowerPoint presentations are often quite heavy, making them difficult to transfer over the network and use on slower PCs and laptops. However, not many people know that the size of almost any presentation can be reduced at least several times. The PPTX format was implemented by Microsoft in Office 2007, but until now, either out of habit or for some other reason, users save presentations in outdated PPT. Saving (or converting) to pptx can significantly reduce the file size.

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How to Compress PPT file

• Upload PPT files to compress.
• Specify the parameters and press the "COMPRESS" button to compress PPT.
• Download the compressed PPT to view instantly or send a link to email.
• Output files will be deleted from our servers after 24 hours and download links will stop working.

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Blog > Compress PowerPoint to reduce the file size

Compress PowerPoint to reduce the file size

02.12.20   •  #powerpointtips.

Sometimes, the file size of your PowerPoint presentation can get very big. In some cases, that can be annoying, e.g. when trying to send the slides via email, but not being able to do so because the file is too large. Usually, pictures and videos are the reason why presentations become too big. The good news are that you can easily compress pictures and embedded media files by following the steps listed below.

Compress images

Compress videos and audios.

• Convert PPT into a PDF file
• Get rid of 3D-models

Compress PPT as ZIP- file

PowerPoint offers the option to compress all images at once or choose single pictures to reduce their file size. Keep in mind, that compressing an image will automatically reduce its quality as well. If you don't need to reduce the file size, better use the highest quality resolution as possible.

There are two ways to compress images within your PPT file which nearly work the same way:

Compress selected pictures

• Select the image you want to compress or any picture if you wish to reduce the size of all graphics
• Navigate to the Picture Tools Format tab and select Compress Pictures

• A new menu pops up. Choose your compression options and make sure to check "Delete cropped areas of pictures" and uncheck "Apply only to this picture" (if you want to compress all images)
• High fidelity: preserves quality of the original picture
• HD (330 ppi): good quality for high-definition (HD) displays
• Print (220 ppi): excellent quality on most printers and screens
• Web (150 ppi): good for web pages and projectors
• E-mail (96 ppi): minimize document size for sharing
• Use default resolution

Compress all images while saving the PPT file

• Open your presentation. Go to File in the PowerPoint menu
• Click Save as and then Browse
• In the window that opens, click on Tools (right beside Save )
• Select Compress Pictures and choose the resolution you need To save even more space, you can additionally choose Delete cropped areas of pictures to remove the parts of pictures which you cropped in PowerPoint.
• Click OK and then Save

Video and audio files can increase your PPT size a lot. It's a good idea to compress those if you want to make some space. Some PowerPoint versions make it possible to decrease the media size in PPT but if this option is missing in your program, online video compressors are the solution.

Compress videos and audios in PPT

• Go to File in the PowerPoint menu
• Open the Compress media drop down
• Choose a compression file size. Don't reduce the quality too much and check if the appearance of your media doesn't look too grainy on the actual projector you will be presenting on

Online video compressor

There are plenty of online video compressors which you can use to reduce the video size in advance. For example, the website FreeConvert makes it easy to decrease the file size without having to download anything. This way you can integrate a smaller media file into PPT.

Links instead of videos

Instead of importing a video to your PPT slides, including a link to your PowerPoint presentation can save a lot of space. If your video is somewhere on YouTube or other online video-sharing platforms, include a link and use it when you're presenting. But notice: a link can only be used, if you're connected with wifi. Watching videos online, can take time and a bad connection might give you some unwanted breaks during your presentation. In this case, saving the video on your disk and opening it separately can save time and still reduce the size of the PPT.

Convert PPT to PDF

By converting a PowerPoint file into a PDF, the size will reduce automatically. During the process, images get compressed and some media (audio, videos, 3D models..) get removed. If you want to change the PowerPoint slides at all time, this method might not be the right one for you, as PDF files can't get edited the way a PowerPoint can. Hence, converting PPT into PDF only makes sense if your presentation will work as a handout and if the PDF files options are enough for you.

• Click Export
• Hit the Create PDF/XPS button
• Choose a location in which you want to save your PDF file
• Click Publish

Get rid of 3D models

The Office 365 subscription makes it possible to add 3D models to your PowerPoint slides. Nevertheless, those media require much space since they transport a lot of information. In order to minimize the PPT file, exchanging the 3D model with a normal image will easily reduce the size of your PowerPoint file.

If you need to share your PPT with someone, a ZIP- file format might help you to reduce the size of the PowerPoint. Even though, this method can save some place temporally, it might not be enough to send it via email. Uploading it to file-sharing platforms, such as GoogleDrive, DropBox, OneDrive or other websites and sharing its link to download the PPT, can be the better option. (Using an USB for sharing the presentation without the need to decompress anything would be the best solution)

Here's how to convert a PPT into a ZIP- file format:

• Select the file you want to minimize in the File Explorer
• Right-Click the file and hit Send to
• Choose the Compressed (zipped) folder option

If you want to decompress a ZIP- file into its original PowerPoint format:

• Right-Click on your ZIP- folder
• Select Extract All... or the similar operation of your program
• Choose a File Location to extract your file to, or extract it at the place you are currently at

How can I reduce the size of a PowerPoint file?

There are several ways to reduce the file size of a PowerPoint. You can compress images, videos and audios, convert your presentation into a PDF file, get rid of 3D models or compress the PowerPoint as a ZIP-file. We explained for you how all of this works in our blog.

How do I compress a video in PowerPoint?

To compress videos in PowerPoint, go to "File" in the PowerPoint menu and then click on "Info". Then open the drop-down menu "Compress media" and select the size of the compression file. Be careful not to reduce the quality too much and check that the quality of your video on the projector you will be presenting on is not too bad.

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Pia Lehner-Mittermaier

Pia works in Marketing as a graphic designer and writer at SlideLizard. She uses her vivid imagination and creativity to produce good content.

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Compress PowerPoint presentation files including PPT, POT, PPS, PPTX, POTX, PPSX, PPTM, PPSM, POTM and many more.

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How to compress document files

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By Andy Greenberg and Matt Burgess

The Mystery of ‘Jia Tan,’ the XZ Backdoor Mastermind

The scourge of software supply chain attacks —an increasingly common hacking technique that hides malicious code in a widely used legitimate program—can take many forms. Hackers can penetrate an update server to seed out their malware, or even break into the network where the software was developed to corrupt it at the source. Or, in the case of one particularly insidious software supply chain attacker known as Jia Tan, they can spend two years politely and enthusiastically volunteering to help.

By Dan Goodin, Ars Technica

Over the weekend, the cybersecurity and open source software community was shocked by the news that a relatively new, experimental version of XZ Utils —a compression utility integrated into many popular distributions of Linux—contained a backdoor that would have allowed hackers in possession of a specific private key to connect to the backdoored system and run their own commands as an administrator. Only some chance detective work carried out by a lone Microsoft engineer, Andres Freund—who’d detected a strange delay in how the remote connection protocol SSH was running in a version of the Linux variant Debian—caught the spy trick before it ended up in many millions of systems worldwide.

That XZ Utils backdoor, it’s now clear, was inserted by none other than the lead open source steward of XZ Utils, a developer who went by the name Jia Tan. In the wake of the backdoor's discovery, a mystery percolating through the tech world remains: Who is Jia Tan, and who did he, or she—or very likely they —truly work for?

Jia Tan exploited open source software’s crowdsourced approach to coding whereby anyone can suggest changes to a program on code repositories like GitHub, where the changes are reviewed by other coders before they’re integrated into the software. Peeling back Jia Tan’s documented history in the open source programming world reveals that they first appeared in November 2021 with the GitHub username JiaT75, then made contributions to other open source projects using the name Jia Tan, or sometimes Jia Cheong Tan, for more than a year before beginning to submit changes to XZ Utils.

By January 2023, Jia Tan’s code was being integrated into XZ Utils. Over the next year, they would largely take control of the project from its original maintainer, Lasse Collin, a change driven in part by nagging emails sent to Collin by a handful users complaining about slow updates. (Whether those users were unwitting accomplices, or actually working with Jia Tan to persuade Collin to relinquish control, remains unclear. None of the users replied to requests for comment from WIRED.) Finally, Jia Tan added their stealthy backdoor to a version of XZ Utils in February of this year.

That inhumanly patient approach, along with the technical features and sophistication of the backdoor itself, has led many in the cybersecurity world to believe that Jia Tan must, in fact, be a handle operated by state-sponsored hackers—and very good ones. “This multiyear operation was very cunning, and the implanted backdoor is incredibly deceptive,” says Costin Raiu, who until last year served as the most senior researcher and head of the global research and analysis team at Russian cybersecurity firm Kaspersky. “I’d say this is a nation-state-backed group, one with long-term goals in mind that affords to invest into multiyear infiltration of open source projects.”

Jeremy White

Karen Williams

As for which nation, Raiu names the usual suspects: China, Russia, and North Korea. He says it’s still too early to know the true culprit. “One thing is for sure clear,” he adds. “This was more cunning than all previous software supply chain attacks I’ve seen.”

A Very Private, Very Busy Programmer

As scrutiny around Jia Tan has mounted since the revelation of the XZ Utils backdoor last Friday, researchers have noted that the persona has remarkably good operational security. Independent security reporter Brian Krebs writes that he could find “zero trace” of Jia Tan’s email address outside of the messages they sent to fellow open source contributors, even after scouring breached databases. Jia Tan also appears to have routed all their communications through a VPN with a Singaporean IP address .

The lack of any other online presence linked to Jia Tan points toward the account being a “single-purpose invented persona” and indicates how much sophistication, patience, and thought was put into developing the backdoor, says Will Thomas, an instructor at the SANS Institute, a cybersecurity training firm. The Jia Tan persona has vanished since the backdoor was discovered, and emails sent by WIRED to a Gmail address linked to it have gone unanswered. Jia Tan’s GitHub account has been suspended, a company spokesperson tells WIRED.

In fact, the only real footprints Jia Tan appears to have left behind were their contributions to the open source development community, where they were a prolific contributor: Disturbingly, Jia Tan’s first code change was to the “libarchive” compression library, another very widely used open source component. That first change swapped one function with a less secure alternative, potentially attempting another malicious code change, notes developer Evan Boehs in his detailed Jia Tan timeline —though the problem has since been fixed.

In total, Jia Tan made 6,000 code changes to at least seven projects between 2021 and February 2024, according to Michael Scott, the cofounder of the cybersecurity firm NetRise who previously worked in the Marine Corps cyberwarfare group under US Cyber Command. Determining all the branching effects of those changes is nearly impossible, Scott says. Because those changes, known as “commits,” are often batched into collections in a process known as “squashing commits,” it’s not always apparent which exact changes were made by Jia Tan. And the difficulty of tracing which of the many versions of a library like libarchive ended up in which software adds yet another layer of obfuscation. “It’s going to be a bit of a mess pulling on this thread and trying to figure out where all these things ended up,” Scott says.

Scott notes that, throughout this time, Jia Tan was also emailing with other contributors, writing in a “very concise, very dry,” but not unfriendly tone that Scott compares to the output of ChatGPT. “Nice job to both of you for getting this feature as far as it is already,” Jia Tan wrote at one point. Or, at another: “Let me know your thoughts on these patches when you have a chance :)” Jordi Mas, a developer who contributed to XZ Utils and had emailed “feedback” from Jia Tan, says in retrospect that the account went to extra levels to build trust in the persona.

Ultimately, Scott argues that those three years of code changes and polite emails were likely not spent sabotaging multiple software projects, but rather building up a history of credibility in preparation for the sabotage of XZ Utils specifically—and potentially other projects in the future. “He just never got to that step because we got lucky and found his stuff,” says Scott. “So that’s burned now, and he’s gonna have to go back to square one.”

Technical Ticks and Time Zones

Despite Jia Tan’s persona as a single individual, their yearslong preparation is a hallmark of a well-organized state-sponsored hacker group, argues Raiu, the former Kaspersky lead researcher. So too are the technical hallmarks of the XZ Utils malicious code that Jia Tan added. Raiu notes that, at a glance, the code truly looks like a compression tool. “It’s written in a very subversive manner,” he says. It’s also a “passive” backdoor, Raiu says, so it wouldn’t reach out to a command-and-control server that might help identify the backdoor’s operator. Instead, it waits for the operator to connect to the target machine via SSH and authenticate with a private key—one generated with a particularly strong cryptographic function known as ED448.

The backdoor’s careful design could be the work of US hackers, Raiu notes, but he suggests that’s unlikely, since the US wouldn’t typically sabotage open source projects—and if it did, the National Security Agency would probably use a quantum-resistant cryptographic function, which ED448 is not. That leaves non-US groups with a history of supply chain attacks, Raiu suggests, like China’s APT41 , North Korea’s Lazarus Group , and Russia’s APT29 .

At a glance, Jia Tan certainly looks East Asian—or is meant to. The time zone of Jia Tan’s commits are UTC+8: That’s China’s time zone, and only an hour off from North Korea’s. However, an analysis by two researchers , Rhea Karty and Simon Henniger, suggests that Jia Tan may have simply changed the time zone of their computer to UTC+8 before every commit. In fact, several commits were made with a computer set to an Eastern European or Middle Eastern time zone instead, perhaps when Jia Tan forgot to make the change.

“Another indication that they are not from China is the fact that they worked on notable Chinese holidays,” say Karty and Henniger, students at Dartmouth College and the Technical University of Munich, respectively. They note that Jia Tan also didn't submit new code on Christmas or New Year's. Boehs, the developer, adds that much of the work starts at 9 am and ends at 5 pm for Eastern European or Middle Eastern time zones. “The time range of commits suggests this was not some project that they did outside of work,” Boehs says.

Though that leaves countries like Iran and Israel as possibilities, the majority of clues lead back to Russia, and specifically Russia’s APT29 hacking group, argues Dave Aitel, a former NSA hacker and founder of the cybersecurity firm Immunity. Aitel points out that APT29—widely believed to work for Russia’s foreign intelligence agency, known as the SVR—has a reputation for technical care of a kind that few other hacker groups show. APT29 also carried out the Solar Winds compromise , perhaps the most deftly coordinated and effective software supply chain attack in history. That operation matches the style of the XZ Utils backdoor far more than the cruder supply chain attacks of APT41 or Lazarus, by comparison.

“It could very well be someone else,” says Aitel. “But I mean, if you’re looking for the most sophisticated supply chain attacks on the planet, that’s going to be our dear friends at the SVR.”

Security researchers agree, at least, that it’s unlikely that Jia Tan is a real person, or even one person working alone. Instead, it seems clear that the persona was the online embodiment of a new tactic from a new, well-organized organization—a tactic that nearly worked. That means we should expect to see Jia Tan return by other names: seemingly polite and enthusiastic contributors to open source projects, hiding a government’s secret intentions in their code commits.

Updated 4/3/2024 at 12:30 pm ET to note the possibility of Israeli or Iranian involvement.

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