Limits by provider
Every figure below comes from the provider’s own help or documentation page, linked in the last column, checked on 7 October 2026.
| Service | Attachment limit | Larger files | Source |
|---|---|---|---|
| Gmail (personal) | 25 MB to send | Added automatically as a Google Drive link | Google: Gmail attachments |
| Google Workspace | Set by the administrator; up to 50 MB (Enterprise Standard) or 70 MB (Enterprise Plus) to receive, after encoding | Google Drive link | Google Workspace: message size |
| Outlook.com | 25 MB | OneDrive file up to 2 GB | Microsoft: Outlook.com sending limits |
| Microsoft 365 / Exchange Online | 35 MB to send, 36 MB to receive by default; admins can set 1–150 MB | OneDrive file up to 2 GB | Microsoft Learn: Exchange Online limits |
| Yahoo Mail | 25 MB for all attachments together, incoming and outgoing | Not stated | Yahoo Help |
| iCloud Mail | 20 MB per message, incoming and outgoing | Mail Drop: up to 5 GB, available for 30 days | Apple Support |
| Proton Mail | 25 MB to send, 50 MB to receive (all attachments together) | Not stated on the page | Proton Support |
| Zoho Mail (free personal) | 20 MB per email, attachments included | Huge Attachments on paid plans: 250 MB to 1 GB | Zoho Mail Help |
Sources: Gmail attachments, Google Workspace message size, Outlook.com sending limits, Exchange Online limits, Yahoo Mail, iCloud Mail limits and Mail Drop, Proton Mail, Zoho Mail.
Two limits are missing on purpose. Google does not state a receive limit for personal Gmail accounts, and AOL’s help pages do not give one for web AOL Mail (only for the AOL Desktop Gold app, 15 MB). We list only what the providers publish.
Why a file under the limit can still bounce
- Encoding makes attachments bigger. Email sends files as text, which adds roughly a third. Microsoft states a 33% increase; Google says about 37% for Workspace limits.
- The limit is usually for the whole message. Yahoo and Proton count all attachments together, and the message text counts too.
- Both sides have limits. The recipient’s mail server may accept less than yours lets you send.
- Outlook on the web sends less than the configured limit. Microsoft notes it allows about 25% below the mailbox setting.
A practical rule: for a 25 MB service, keep attachments under about 18 MB in total; for 20 MB services, under about 14 MB.
How to get a PDF under the limit
- Compress it to a target size, such as 2 MB, 1 MB or 500 KB. The tool tries the gentlest method first.
- Remove pages the recipient does not need, such as blank pages or appendices.
- Split the PDF into parts and send them in separate emails.
- Share it with your provider’s cloud link (Google Drive, OneDrive, Mail Drop) when it must stay large.
For more on shrinking files for upload forms and email, read how to compress a PDF and how to reduce a PDF for an upload limit.
People also ask
Common questions
What is the Gmail attachment size limit?
For personal Gmail accounts it is 25 MB. Larger attachments are automatically turned into a Google Drive link. Work and school accounts follow limits set by the Google Workspace administrator.
What is the Outlook attachment size limit?
Outlook.com allows attachments up to 25 MB, or up to 2 GB as a OneDrive file. Microsoft 365 work and school mailboxes default to 35 MB to send and 36 MB to receive, which an administrator can change.
Why is my 20 MB file rejected by a 25 MB limit?
Attachments are encoded for sending, which makes them roughly a third larger (Microsoft cites 33%, Google about 37% for Workspace). The limit can also apply to all attachments together, and the recipient’s server may accept less than yours sends.
Does the recipient’s limit matter?
Yes. A message has to fit the limits on both sides. Proton Mail, for example, accepts 50 MB incoming but sends only 25 MB, and company mail servers often set their own caps.
How do I send a PDF that is too big?
Compress it first, ideally to a specific size such as 2 MB or 1 MB, remove pages you do not need, split it into parts, or share it through your provider’s cloud link instead of attaching it.
Do these limits change?
They do, occasionally. Each limit on this page links to the provider’s own help page so you can check the current figure.