What's Gmail's attachment limit?

Google says personal Gmail accounts can attach up to 25 MB in total. Above that, Gmail automatically replaces the attachment with a Google Drive link. Work and school accounts can have limits set by their administrators.

Why won't a 20 MB file go through my company email?

Microsoft says the default message size for Exchange (business) accounts is 10 MB, counting both attachments and the message itself — and each organisation's administrators may set it differently.

Does shrinking a file lower its quality?

It depends. Text PDFs usually shrink with almost no visible change; scans, photos and videos show more difference the harder you compress them. Always open the smaller file before you send it.

File too big to email? Gmail, Outlook and Yahoo attachment limits, and how to shrink files

You hit Send and get "file too large", or the email bounces back. It happens a lot with quotations, scanned documents and video clips. Here are the limits of popular email services, taken from their own help pages, and how to make your files fit.

Attachment limits by service

Service	Max attachment size	If you go over
Gmail (personal account)	25 MB	Automatically becomes a Google Drive link
Outlook.com on the web	25 MB	Attach from OneDrive, up to 2 GB
Outlook app (internet accounts such as Outlook.com or Gmail)	20 MB (default)	Can't send
Company email on Exchange	10 MB (default)	Can't send; administrators may set it differently
Yahoo Mail	25 MB, incoming and outgoing	Can't send or receive

These are the total of all attachments in one email, and Microsoft notes Outlook's limit includes the message itself.

Remember that the recipient has limits too. Send a 20 MB file from Gmail to a company mailbox that accepts only 10 MB and it won't arrive.

Why files grow when you send them

Email carries only text, so attachments are converted to text before sending. Under the MIME standard (RFC 2045), Base64 encoding makes the data about 33% larger.

Some systems count the size after encoding — Google Workspace says its receiving limits apply after encoding, which adds about 37%. A file close to the limit may therefore fail, so aim comfortably below it.

Shrink files without uploading them

The tools below run in your browser, so your files are never uploaded — a good fit for documents with personal or customer data.

PDF documents

Compress PDF has two levels: keep quality for normal documents and strong for scans, which are often huge.
Still too big? Split the PDF and send it in several emails.

Photos

Phone photos are usually far bigger than needed for viewing on a screen. Resize them to 50% or to a set width in pixels, then check they're still sharp enough.
Compress images to cut file size, many at once.
Sending several photos? Put them in one file with images to PDF.

Video

Compress video lowers the resolution and saves an MP4 that plays everywhere.
Only need part of it? Trim the clip first — the file gets much smaller.
Only need the sound? Use video to MP3.

When it's still too big

Long videos and design files often can't be shrunk to a few dozen MB. Send a link instead of an attachment: Gmail does this automatically with Google Drive, and Outlook.com can attach OneDrive files up to 2 GB.

Before sharing a link, check who can open it — especially for documents with personal data.

Note

The figures here come from Google, Microsoft and Yahoo help pages and RFC 2045, read on 28 September 2026. Providers can change their limits, and work or school accounts depend on their administrators' settings.