---
title: "Attachments"
description: "Pick them with the paperclip, paste them in or drop them anywhere on the composer. A pasted image lands in the body rather than the file list. On Nextmail mailboxes incoming files sit in object storage, one object each, and a file is fetched only when you open or download it."
url: "https://nextmail.sh/docs/knowledge/writing/attachments"
area: "Knowledge base"
category: "Writing & sending"
status: "live"
---

# Attachments

Pick them with the paperclip, paste them in or drop them anywhere on the composer. A pasted image lands in the body rather than the file list. On Nextmail mailboxes incoming files sit in object storage, one object each, and a file is fetched only when you open or download it.

## Details

- The paperclip takes several at once, of any type except the ones mail servers refuse to carry, such as .exe, .bat, .js and .msi files. PNG, JPEG, GIF and WebP pasted or dropped into the message body are embedded there as inline images rather than attached. Dropped anywhere else on the composer, any file attaches. A file over 5 MB is uploaded to Files first and attached from there, so a saved draft keeps it without carrying its bytes.
- Files carried inside the message come to at most 25 MB, the largest size most mail servers accept once the files are encoded, and an API call that sends the bytes of its attachments takes up to 10 MB of them. Past 25 MB the files go as download links instead, even without a files domain. Once a files domain is active, a message whose files come to more than 2 MB carries them as links on its own, and the API can link a file already in the workspace at up to 100 MB each and 250 MB a message.
- Images can be compressed on the way out (Low, Medium or Original), and already-attached files are re-processed when you change it.
- Opening a thread lists each attachment by name and size and fetches none of them: a file is read when you open or download it, and forwarding a message fetches its files to send them on. A message you sent keeps its attachments too, so downloading one back out of Sent works. Two things still come back empty: anything sent before that was true, and a file since deleted from Files.