The short version

Drop the PDF and press the button. The tool works in three stages, cheapest first, and stops at the first one that gets the file under 90 MB.

Images are recompressed in place first, so text, links and forms stay exactly as they were. Only when a file still will not fit are the pages rebuilt as images, and even then an invisible text layer keeps the words searchable. A file already under the cap is handed back untouched. If your file is already small enough, you do not need this tool.

Most PDFs never come near 100 MB, so this target mostly matters for the photo-heavy ones: a property brochure, a site inspection report with two hundred photographs, a wedding album, a full-resolution portfolio. Those can start well above the cap, and the ladder brings them under it with photographs that still look like photographs.

Where the 90 MB limit comes from

Who asks for itPlaces that cap uploads at 90 MB
  • WhatsApp document attachments100 MB, sender-side check
  • Safe target for reliable delivery and preview90 MB
  • WhatsApp Business, configurable by the account ownermay be lower
  • Broadcasts and large groupseffective ceiling sometimes lower
  • Photos sent as images rather than documentsrecompressed heavily by WhatsApp

Caps like this are rarely revisited once set. They are written into a portal's upload form at launch, sized for the storage and bandwidth of the day, and outlive both. The practical response is not to argue with the number but to produce a file that clears it while staying readable, which is what the ladder below does.

How the tool hits 90 MB

1

Add the PDF

Drop it or browse. It is read into browser memory; nothing is uploaded, so a slow connection makes no difference.

2

Stages one and two: tidy, then the images

Unused objects, thumbnails and stale metadata go first, which costs nothing at all. Then the pictures inside the file are recompressed in place, starting at 200 ppi, while your text, links and form fields are left exactly as they were.

3

Stage three, only when it is needed

If the images were not where the weight was, the pages are rebuilt as pictures with an invisible text layer behind them, so the words stay searchable. It probes at 150 dpi, works out the resolution that should fit, and will not go below 60 dpi.

4

Download, and read the result line

It shows the final size and which stage produced it. If none fitted, you still get the smallest attempt, labelled honestly, rather than a file that silently missed the target.

The image ladderSeven rungs, from 200 ppi down to 60
200q82150q75120q66100q5880q5072q4260q36Rung 1: images barely touched (ppi above, JPEG quality below)Rung 7: visibly softYour text, links and form fields are untouched at every rung
Stage two walks down this ladder, recompressing the pictures inside the file and leaving everything else alone. It stops at the first rung under 90 MB, and abandons the ladder early when the images are not what is making the file big.
Stages
Three

Structure, then the images in place, then the pages as pictures. It stops at the first stage that fits.

Text after compression
Kept

Untouched at the first two stages. If the pages do get rebuilt, an invisible text layer keeps them searchable.

Bytes uploaded
0

The IDs, forms and statements people compress for portals never leave the device.

What fits in 90 MB, and what does not

The honest answer depends on page count and on what is on the pages. Text pages are cheap because a rendered page of black text compresses extremely well as a JPEG. Colour scans and photographs are expensive because every pixel carries information the encoder has to keep. The estimator uses typical figures to show which attempt your file is likely to land on.

Try it

Will your file fit in 90 MB?

Enter the page count and what the pages contain. The estimate shows the attempt that is likely to succeed and what that attempt looks like.

Typical sizesCommon documents against the 90 MB line
1000-page text documentabout 42 MB200-page colour scanabout 48 MB500-page report with imagesabout 55 MB200 full-page photosabout 76 MB90 MB
Estimates for the first attempt, before any quality is traded away. Anything past the line will step down the ladder.

When it cannot reach 90 MB

Some documents will not fit legibly, and the tool says so rather than pretending. When the result line reports a miss, three moves usually solve it:

  • Split first. Use Split PDF to break the file into parts and compress each. Most portals accept several attachments even when each one is capped at 90 MB.
  • Rescan the source. A fresh 150 dpi greyscale scan compresses far better than a colour scan that has already been through one compressor. Every pass costs quality, and the first pass should start from the cleanest source.
  • Check the real limit. Portals sometimes state one number and accept another. Read the fine print, or try a slightly larger file before compressing harder than you need to.
One pass, from the original
Compressing an already-compressed file compounds the quality loss without much further saving. If the first result is not right, run the original again rather than the output. And keep the original: the compressed copy is for the portal, not for your records.

Send photos as a PDF document, not as images

WhatsApp recompresses every image sent as a photo, hard. A 4 MB picture arrives as a few hundred kilobytes with visible artefacts, and there is no setting to prevent it. A file sent as a document is transferred as it is. So the way to deliver photographs at quality on WhatsApp is to put them in a PDF and send the PDF as a document.

Two ways to send photosOnly one of them keeps the quality
Sent as imagesRecompressed to a fraction of the sizeVisible artefacts on detailArrive as a loose set, in any orderNo setting turns this offSent as a PDF documentTransferred byte for byteYour chosen quality is what arrivesOne file, in the order you setOpens in any reader on any phone
Build the PDF with Images to PDF, bring it under 90 MB here if needed, and attach it with the document option.
Why 90 MB and not 100
Files close to the ceiling sometimes transfer and then fail to preview on lower-end Android phones, and business accounts and large groups can enforce a lower limit than the app advertises. Ten megabytes of headroom costs almost nothing in quality and removes the edge cases.

Where people use the 90 MB target

Typical jobsWhat gets compressed to this size
  • Property brochures to prospective buyersphotos, fits
  • Wedding and event albums shared with familyphotos, attempt 1 or 2
  • Site inspection and engineering reportsphotos and text
  • Full-quality design portfoliosimages

Why this runs in your browser

The files people compress for portals are the ones that identify them: passports, ID cards, certificates, bank statements, tax forms. Uploading them to a compression website in order to upload them again to the portal doubles the exposure for no benefit.

Two ways to compressOne of them never transmits the document
Your devicePDFin memoryBrowser enginecompressDownload0 bytes leavethe machineTypical online toolPDFon diskuploadServercopies filedownloadA full copy now sits on hardware you do notcontrol, under a policy you cannot audit
PDF.js renders the pages and pdf-lib rebuilds the file inside the tab. The document is read into memory, compressed there, and offered as a download.

The tool is right above

Everything on this page runs in your browser. Scroll up, drop the file, and keep it on your machine.

Jump to the tool

Common questions

The questions people have with a 90 MB cap in front of them.

01Why not exactly 100 MB?

Files at the ceiling occasionally transfer and then fail to open on the receiving phone, and business accounts or groups may enforce a lower limit. Targeting 90 MB avoids the edge cases with no visible cost.

02Can I send the photos as images instead?

You can, and WhatsApp will recompress each one heavily with no way to prevent it. Sending them inside a PDF as a document preserves the quality you chose.

03Will the text still be readable?

For text documents, yes, and usually at the first attempt. For colour scans and photo-heavy pages, later attempts soften the image visibly. The result line tells you which attempt produced the file, and the estimator above predicts it.

04Will the text still be selectable?

Usually, yes. The first two stages leave the text exactly as it was. If the file only fits by rebuilding the pages as pictures, an invisible text layer goes behind them so the words can still be searched and copied.

05What if the file cannot get under 90 MB?

You still get the smallest attempt, with the result line stating the final size honestly. Split the file into parts, or rescan the source in greyscale at a lower resolution, and try again.

06My file was already small. Why did it grow?

The tool checks the size first and hands a file that already fits straight back, untouched. If the file is already under the cap, send it as it is.

07Are my files uploaded anywhere?

No. Rendering and compression run in your browser. The file never leaves the device.

08Is it free?

Free. Every tool, unlimited use, no signup.