# Limits & requirements

Source: https://help.strongfolder.com/en/limits/
Updated: 2026-11-05

> StrongFolder sets no limit on file size, number of files or transfers. What limits a transfer in practice is the recipient's free disk space, both connection speeds, and how long the sender keeps the tab open. Saving a whole folder with its structure needs Chrome, Edge or Opera on a computer.

## Is there a file size limit?

No. No size limit set by StrongFolder. The practical limits are free disk space on the recipient's device, connection speed, and how long both devices stay online.

**Key facts**

- **File size:** no limit set by StrongFolder.
- **Number of files and transfers:** no limit set by StrongFolder.
- **Price:** Free, no account needed.
- **Sender:** keeps the tab open until the recipient finishes.
- **Whole folders:** saved with structure in Chrome, Edge, Opera (computer).

## What actually limits a transfer?

| Factor | Why it matters | What to do |
|---|---|---|
| Recipient's free disk space | The files are written to their disk | Check space before a large send |
| Sender's upload speed | A direct transfer can't be faster than it | Use a wired connection; avoid big uploads at the same time |
| Time both devices stay online | Files come from the sender's device | Keep the computer awake and the tab open |
| Recipient's browser | Saving whole folders needs the File System Access API | Recipient opens the link in Chrome, Edge or Opera on a computer |
| Network restrictions | Some networks block WebRTC | Another network, or ask the administrator |

## Which browsers are supported?

| Task | Chrome / Edge / Opera / Brave (computer) | Firefox (computer) | Safari (Mac) | Mobile browsers |
|---|---|---|---|---|
| Send files | Yes | Yes | Yes | Yes, keep the tab on screen |
| Send a folder | Yes | Yes | Yes | Depends on the phone's file picker |
| Download single files | Yes | Yes | Yes | Yes |
| Save a whole folder with structure | **Yes** | ZIP or file by file | ZIP or file by file | ZIP or file by file |
| Chrome extension | Chrome and most Chromium browsers | — | — | — |

Browsers change quickly; if something does not work, update the browser first.

## Why must the sender stay online?

Because the files are on the sender's device, not on a server. The sender's browser tab must stay open and online until the recipient finishes downloading — files come from the sender's device, not from a server. This is
the price of not uploading and not storing your files. When you can't stay online, a cloud
link is the right tool — see [Why the sender must stay online](https://help.strongfolder.com/en/guides/why-sender-stays-online/).

## What about long file names and paths?

Windows limits the length of a full file path. If a received file's path would be too long,
StrongFolder shortens the name and adds a text file listing every renamed file, so nothing is
lost silently.

## Are there limits on what I may send?

Only send files you have the right to share. The [Terms of Use](https://help.strongfolder.com/en/terms-of-use/) apply to all
transfers.

[Send files now](https://strongfolder.com)

## FAQ

### What is the maximum file size?

There is none set by StrongFolder. People send files from a few kilobytes to hundreds of gigabytes. The recipient needs enough free disk space.

### Is there a limit on the number of files?

No limit is set by the service. Folders with many thousands of files work; very many tiny files transfer slower than one big file of the same total size.

### How long does the link work?

The link works while the sender keeps sharing. When the sender clicks Stop Sharing or closes the tab, the files are no longer available.

### Does it work on a phone?

Yes, in a mobile browser — but phones pause background tabs, so keep the StrongFolder tab on screen during the transfer. Saving whole folders with their structure needs a computer.

### Can I resume an interrupted transfer?

If the connection drops, start the download again from the link while the sender is still sharing.

### Does StrongFolder work behind a corporate firewall or VPN?

Usually yes. If a direct connection is blocked, the encrypted stream goes through a StrongFolder relay server. Some networks block WebRTC entirely; then try another network or ask the administrator.