Gmail Attachment Size Limit: 25 MB, the 33% Tax, and How to Get Around It
The Gmail Attachment Size Limit Is 25 MB — With Two Asterisks
The Gmail attachment size limit most people hit is 25 MB to send. That number is correct for personal Gmail and for most Google Workspace accounts. It is also the number that produces the most confusion, because a file that looks like 22 MB on disk is routinely rejected.
Two things sit between the advertised cap and a delivered message:
- Base64 encoding inflates every attachment by about 33% before it is transmitted.
- The recipient's limit can be lower than yours. Gmail can receive 50 MB; plenty of corporate inboxes cannot.
The smallest number in that chain wins. This is the same pattern as the Outlook attachment size limit, just with Google's numbers instead of Microsoft's.
Gmail Attachment Size Limit by Account Type
| Account | Send limit | Receive limit | Can it be raised? |
|---|---|---|---|
| Personal Gmail (@gmail.com) | 25 MB | 50 MB | No |
| Google Workspace (most editions) | 25 MB default | 50 MB default | Yes — admin |
| Google Workspace Enterprise Plus | 25–50 MB (admin) | 70 MB | Yes — admin, not on by default |
| Gmail accessed via another client | 25 MB | 50 MB | No — Gmail's server still enforces it |
The Enterprise Plus increase landed in February 2026. Administrators set a message size between 25 MB and 50 MB in 5 MB steps. Users cannot raise it themselves, and third-party outbound relays often still reject anything above 25 MB, so turning the dial up is not a free pass.
For everyone else, including every personal Gmail account, 25 MB is the send ceiling and it is not moving.
A roundup of other providers lives in the complete guide to email attachment size limits. This page is the Gmail-specific version: the numbers, the encoding trap, the Drive-link behaviour, and the mailbox quota that silently sits behind all of it.
The 33% Tax That Makes 25 MB a Lie
Email cannot carry raw binary. Attachments are Base64 encoded, which represents every 3 bytes as 4 characters — an increase of roughly 33% before the message leaves your browser.
| File on disk | Size as transmitted | Passes a 25 MB send limit? |
|---|---|---|
| 15 MB | ~20 MB | Yes |
| 18 MB | ~24 MB | Just barely |
| 20 MB | ~27 MB | No |
| 24 MB | ~32 MB | No |
Against the stated Gmail attachment size limit, your real working ceiling is about 18 MB. Size the file against that number, not 25. Multiple attachments share one budget, and HTML signatures eat a little more.
That is also why "it was 24 MB and Gmail still bounced it" is the normal case, not a bug.
What Gmail Does When You Go Over
Gmail does not bounce the message back at you with a scary error the way a lot of corporate servers do. It strips the attachment and inserts a Google Drive link instead.
That is convenient until it is not:
- The recipient needs permission to open the Drive file. External clients frequently hit a sign-in wall.
- The original file still lives in your Drive, counting against the 15 GB shared quota.
- A Drive link is not an attachment. Some submission portals, ticketing systems, and legal workflows reject links on principle.
- Drive links do not expire, which is a feature for collaborators and a liability for anything confidential sitting on a forwarded thread.
If the goal is "this file in their inbox," a Drive link is a different product. Compressing until the file actually attaches is the one that preserves the original behaviour.
The Gmail Mailbox Size Limit Is Not a Separate Number
Searchers looking for a Gmail mailbox size limit are usually hitting a different wall: they can no longer send or receive attachments because Google storage is full.
There is no dedicated Gmail mailbox quota. Storage is the 15 GB (free) pool shared across:
- Gmail (messages and attachments)
- Google Drive
- Google Photos
Paid Google One and Workspace plans raise the pool; they do not split it. A library of original-quality phone photos will fill the 15 GB long before your inbox looks "full," and Gmail then refuses new attachments. Google's own help pages are explicit: when you reach the storage limit, you cannot send or receive attachments.
If Photos is the hog, compressing before upload is the same move as compressing photos for Google Photos — Storage Saver will re-encode for you, irreversibly, or you can compress first and keep control of the quality.
How to Get Under the Gmail Attachment Size Limit
Work these in order. Most people skip the first one and go straight to Drive.
1. Compress the file so it fits
This is the only option that keeps a genuine attachment. It is also the one that works, because the files that miss 25 MB are almost always video, photos, or image-heavy PDFs — formats that shrink dramatically when re-encoded.
| File | Typical original | After sensible compression | Fits in Gmail? |
|---|---|---|---|
| 4K phone video, 2 min | 250–400 MB | 12–25 MB | Usually |
| 1080p screen recording, 5 min | 150–300 MB | 10–20 MB | Usually |
| 40 camera JPEGs | 180 MB | 25–40 MB as a set; ~8–15 MB more aggressively | Split or compress harder |
| PDF with embedded photos, 40 pages | 45 MB | 8–15 MB | Yes |
| Excel workbook with images | 30 MB | Often 5–12 MB | Yes — see compress an Excel file |
ZIP and 7z do not help for MP4, JPEG, PNG, HEIC, or already-compressed PDFs. Those formats have no redundancy left. Archiving a 30 MB video typically saves under 2%. For media, you have to re-encode, not wrap. WinRAR for Mac and Finder's Compress are the wrong tool for this job; they are the right tool for documents, project folders, and logs.
On a Mac, Compresto compresses video, images, and PDFs locally with a target-size option, which is the practical way to aim at that 18 MB working ceiling. Nothing is uploaded. For a walkthrough aimed at mail specifically, see reduce file size for email attachments and compress video for email. If you need a hard cap, compress a video to 25 MB is the same problem with the number in the title.
2. Let Gmail insert a Drive link
Attach the file anyway. When it is over the Gmail attachment size limit, Gmail uploads it to Drive and swaps in a link. Confirm sharing is set to "anyone with the link" or to the specific recipient — the default is often too tight for people outside your organisation and too loose for anything private.
Use this when the file genuinely cannot get under ~18 MB (a CAD package, a raw project, an uncompressed archive) and the recipient is fine clicking a link.
3. Use a transfer link instead of email
For files that need to stay large — a ProRes master, a client dump, a folder of RAWs — email is the wrong channel. A dedicated transfer service or a cloud share is faster than pretending Gmail will carry it. WeTransfer alternatives and how to send large video files cover that path. Compressing first still helps: a 2 GB upload that becomes 80 MB is a better experience on both ends even when you are not attaching it.
What Does Not Raise the Gmail Attachment Size Limit
- A Google One storage upgrade. Extra terabytes do not change the 25 MB send cap. They only stop the "storage full" failure.
- Gmail offline, the desktop site, or the mobile app. The limit is on Google's mail servers. The client is not what is blocking you.
- Splitting into 24 MB chunks by hand. Recipients hate this, mail filters hate this, and Base64 will still push each chunk over if you sized them against 25 MB instead of 18 MB.
- Renaming the file. Gmail is looking at encoded size, not the extension.
FAQ
What is the Gmail attachment size limit?
Personal Gmail accounts can send 25 MB and receive 50 MB per message. Most Google Workspace editions use the same defaults. Enterprise Plus can go to 50 MB send and 70 MB receive if an administrator enables it.
Why does Gmail reject a file that is under 25 MB?
Base64 encoding adds about 33%. A 20 MB file is ~27 MB on the wire. Plan for an 18 MB on-disk ceiling against a 25 MB cap. Several smaller files that add up to 25 MB will fail the same way.
How do I send a file larger than 25 MB in Gmail?
Compress it so it attaches, or let Gmail convert it to a Google Drive link. Compression is better when the file is video, photos, or a PDF. A Drive link is better when the file cannot shrink and the recipient can open Drive.
Does Gmail compress attachments?
No. Gmail does not re-encode video or recompress images. Oversized files become Drive links. Compression has to happen before you attach.
What is the Gmail mailbox size limit?
There isn't a separate mailbox cap. Gmail shares 15 GB (or your paid quota) with Drive and Photos. When that pool is full, sending and receiving attachments stops even if the message itself is tiny.
Make the File Fit
The Gmail attachment size limit has been 25 MB for years. Cameras and screen recordings have not. Waiting for Google to raise the personal-account cap is not a workflow.
Compresto compresses the files that actually miss that cap — video, images, and PDFs — natively on macOS. Batch a folder of attachments, set a target size under 18 MB, and keep the result off Google's servers until you choose to send it.