---
title: "Email attachments and size limits"
description: "Attach files with the paperclip or by pasting, drop images into the body, and let big sets go as download links. Files inside a message cap at 5 MB."
url: "https://openemail.uk/features/attachments"
---

[Writing & sending](https://openemail.uk/features.md#writing)

# Attachments Picked, pasted, or linked.

Attach with the paperclip or by pasting, and drop images into the body. Sent keeps a copy you can download again.

[Open mail](https://openemail.uk/mail/inbox) [Get Started](https://openemail.uk/signup.md)[All features](https://openemail.uk/features.md)

In short

## What is an email attachment?

An attachment is a file carried inside the message, encoded as text beside the body. Every copy carries the whole file, so mail services cap message size and big files often travel as download links.

5 MB

of files carried inside one message

2 MB

above which a files domain sends links

100 MB

per linked file, through the API

How it works

## How it goes in decides where

The paperclip and paste attach files. A PNG, JPEG, GIF or WebP dropped or pasted into the body is embedded there. Other drops are ignored.

## Small files ride along, big ones link

Files inside a message are capped at 5 MB together. On Automatic, the default, a set over 2 MB goes as links once a files domain is active.

## Shrink images, or keep the originals

Low and Medium fit images inside 1920 × 1080. Original leaves them alone, and switching re-processes files already attached.

## What the paperclip offers

The picker suggests these. Pasting attaches anything else.

image/\* any image .pdf PDF .doc .docx Word .xls .xlsx Excel .txt plain text

What you get

## In the product today

Forgotten-file check

Mention an attachment in English with none added, and Send asks first.

Download all

Every attachment on a message saves as one zip.

Text opens in place

Up to 512 KB they show in a viewer, and other files offer a download.

Good practice

## Getting the most out of it

1. 01
   
   Pick, do not drag
   
   A drop only takes images, so use the paperclip for everything else.
2. 02
   
   Add a files domain
   
   Automatic only swaps sets over 2 MB for download links once one is active.
3. 03
   
   Original for fine print
   
   Low and Medium fit images inside 1920 × 1080, which can blur fine text in scans.

Where it stands

## Good to know

Questions

## Asked often

Keep going

## Works well with

Files

Every attachment this mailbox holds, in one place you can search, download and clear out.

Your mail on object storage

Full message bodies and attachment bytes on R2, indexed per mailbox.

Drafts

Autosaved three seconds after you stop typing, and reopened from the Drafts folder with the recipients, the subject, the body and the From address intact. The attachments stay behind.

Start

## Your domain, your mail.

Point a domain at OpenEmail and read it in a mailbox built around it. The free plan covers one domain.

[Open mail](https://openemail.uk/mail/inbox) [Get Started](https://openemail.uk/signup.md)[Read the reference](https://openemail.uk/docs/knowledge/writing/attachments.md)