How to Compress a PDF on iPhone and Android
You're on your phone, you need to send a PDF, and it's too large for email. The good news: you don't need a computer or an app to fix it. You can compress a PDF directly from your iPhone or Android browser in under a minute, completely free, without installing anything.
Here's exactly how to do it on both iOS and Android.
In short
- ✔ Works on iPhone, iPad, and all Android devices
- ✔ No app download required — runs in Safari, Chrome, or any browser
- ✔ Upload from Files, iCloud Drive, Google Drive, or Downloads
- ✔ Free, no account needed
How to compress a PDF on iPhone (Safari)
Open the compressor in Safari
Open Safari and go to the PDF compressor. Tap the upload area — your iPhone will let you pick from the Files app, iCloud Drive, or any other connected storage.
Choose the compression level
Select medium for the best balance of size and quality. If you need the smallest possible file, choose high compression. The result is typically 50–70% smaller than the original.
Download to your iPhone
Tap compress and then download. Safari saves the file to your Downloads folder in the Files app. From there you can attach it to an email, share it via WhatsApp, or upload it anywhere.
How to compress a PDF on Android (Chrome)
Open Chrome on your Android device and navigate to the compressor. Tap the upload area to open the file picker — you can browse your Downloads folder, Google Drive, or any connected storage. Select your PDF, choose the compression level, and download the result.
The compressed file saves to your Downloads folder and can be opened in Chrome, shared via the Android share sheet, or attached to an email directly from the Gmail or Outlook app.
Does iOS have a built-in way to compress PDFs?
No. iOS can view and share PDFs, but it has no native option to compress them. The Files app and Safari can open PDFs, but neither offers a reduce-file-size function. For most iPhone users, a browser-based compressor is the only free option that doesn't require an app download or a subscription.
Some PDF apps in the App Store offer compression, but most are either paid or limit free usage to a small number of files per month. A browser-based tool has no such restrictions — you can compress as many PDFs as you need, completely free.
How to send the compressed PDF from your phone
Once the compressed file is in your Downloads folder, you have several options:
- Email: open your mail app and attach the file from the Downloads folder in Files (iOS) or the file picker (Android)
- WhatsApp: open a chat, tap the attachment icon, select Document, and browse to Downloads
- AirDrop (iPhone): long-press the file in the Files app and tap Share → AirDrop
- Google Drive / Dropbox: upload directly from the Files app or the Drive/Dropbox app
Frequently asked questions
Does it work on older iPhones?
Yes. The tool runs entirely in the browser and doesn't require any specific hardware features. As long as Safari can load a webpage and upload a file, it will work — regardless of how old the iPhone is.
Where is the compressed file saved on my iPhone?
Safari saves downloads to the Downloads folder in the Files app by default. You can change this location in Settings → Safari → Downloads. Once it's in Files, you can move it anywhere — iCloud Drive, On My iPhone, or any connected service.
Is there a file size limit for mobile uploads?
The tool handles files up to 100MB. Very large files will take longer to upload on a slower mobile connection — a Wi-Fi connection is recommended for files over 20MB.
Can I compress a PDF received by email on iPhone?
Yes. In Mail, long-press the PDF attachment and tap Save to Files. Once it's in the Files app, you can upload it to the compressor. After downloading the compressed version, attach it to a new email.
Compress PDF from your phone
Free, no app needed. Works on iPhone, iPad, and Android.
Compress PDF — free