Compress PPT — Reduce PowerPoint File Size

Make a .pptx small enough to email or upload.

PPTX
up to 25 MB per file
Deleted after 30 minutes

What Compress PPT does

Make a .pptx small enough to email or upload. The pictures inside the deck are re-encoded and capped at 1920 px on the longest edge; slides, text, layouts, animations and notes are not touched.

Whether you call it a PPT compressor, a PowerPoint compressor or a way to reduce PPT file size, it is this tool: it compresses a PowerPoint (.pptx) file online for free, without an account, by re-encoding the pictures inside the deck.

Where a deck's size comes from

Part of the file	Share of a typical 40 MB deck	What compression does
Photos and screenshots	85–95%	Re-encoded as JPEG at a chosen quality; oversized ones scaled to 1920 px
Slide XML, text, shapes	1–3%	Untouched
Embedded fonts	0–5%	Untouched
Video and audio	0–90%	Untouched — compress these before inserting

Which is why an image-heavy deck drops by half or more and a text-only deck barely changes.

How it works

01
Upload your .pptx file
Select the PowerPoint deck you want to make smaller (up to 25 MB).
02
Select compression level
Choose how much you want to reduce the file size.
03
Download your compressed file
Your smaller PowerPoint is ready for download instantly.

When you'd use it

A deck too large to email or upload to the LMS
Sharing a photo-heavy presentation on a slow connection
Fitting a deck under a conference's upload limit

Formats and limits

Accepts: .pptx
Produces: Compressed PPTX
Files per run: One
Size limit: 25 MB per file

Limitations

Compression re-encodes the pictures inside the deck; slides, text, animations and layouts are untouched. A deck that is large because of embedded video or audio will not shrink.
Pictures are downscaled to what a 1920-px-wide slide needs; if you zoom into an image in slide-show mode it will look softer than before.

What happens to your file

Processed over an encrypted connection and deleted after 30 minutes.

Full detail in the Privacy Policy.

Questions

What is the maximum file size I can compress?

Up to 25 MB per file, which is the server upload limit. A deck larger than that is usually carrying video or audio, which this tool does not compress — remove or compress those first, then upload.

Does compressing a PPT affect image quality?

Only slightly, and usually invisibly. Pictures are re-encoded as JPEG at high quality and capped at 1920 px on the longest edge — more than a projector or laptop screen shows. Pictures with transparency stay PNG, and nothing else in the deck is changed.

Can I compress a PPTX file without PowerPoint installed?

Yes! DocsBolt runs on the web, so you never need PowerPoint or any other software installed — just upload, compress, and download.

Why is my PowerPoint file so large?

Almost always the images: photos inserted at full camera resolution, screenshots pasted at retina scale, or one background image duplicated across every slide. A 40 MB deck rarely has 40 MB of content — it has a handful of oversized images that compression brings down to what a screen actually displays.

What size does my PPT need to be for email?

Gmail and Outlook cap attachments at about 25 MB, and many university portals and LMS uploads sit at 8 to 20 MB. If your deck is over the limit, compress it here first — image-heavy presentations typically shrink by half or more, which is usually enough to get under an attachment cap without visible quality loss.

What exactly does the compressor change inside the .pptx?

Only the pictures in ppt/media. Each one is re-encoded as JPEG (or kept as PNG when it has transparency) and downscaled so its longest edge is at most 1920 px, which is what a Full HD slide can show. Slide XML, text, layouts, masters, animations, notes and embedded fonts are copied through untouched, so the deck opens exactly as before.

Why did my deck not reach the target size?

Because something other than pictures is taking the space: embedded video or audio, a very large number of slides, or fonts embedded in the file. The result card says when the target could not be reached and how far it got; for video-heavy decks, compress or link the videos separately.

Will the compressed deck still open on older PowerPoint versions?

Yes. The file structure is not rewritten — the same OpenXML parts remain, only the image bytes inside them change — so anything that opened the original opens the compressed copy.