# temp.cool vs Onetime Secret

> Both send a secret that can be read once. temp.cool encrypts in your browser so its server never sees the text, and stores everything in the EU; Onetime Secret is open source, lets you pick an EU or US data region, and offers custom domains on paid plans.

1. **Where encryption happens** temp.cool encrypts in your browser and only ever receives scrambled text. Check Onetime Secret's own docs for how and where it encrypts.
2. **Where data lives** temp.cool stores messages in the EU only. Onetime Secret lets you choose between data regions, including the EU.
3. **Open source** Onetime Secret's code is public, so you can run your own copy. temp.cool is a hosted service.

## At a glance

| | temp.cool | Onetime Secret |
|---|---|---|
| Free to use, no account | Yes | Yes |
| Encrypted in your browser before sending | Yes | See their docs |
| Data location | EU only | Choice of regions, incl. EU |
| Password on the link | Yes, destroyed after 4 wrong tries | Yes |
| Views per link | 1 to 10 | 1 |
| Link preview protection | Yes, needs a tap | See their docs |
| Open source, self-hostable | No | Yes |
| Your own domain | Paid plans | Paid plans |
| Languages | English, Dutch | Several |

We checked Onetime Secret's public documentation in October 2026. Features change, so check their site for the latest.

## Pick temp.cool if

- You want the server to never see the secret, not even for a moment.
- You need data to stay in the EU without choosing a region.
- People open your links in WhatsApp, Slack or Teams, where previews can burn a one-time link.
- You want to share a secret with a small group, up to 10 views.

## Pick Onetime Secret if

- You want to run the software yourself on your own servers.
- You need a data region outside the EU.

## How temp.cool's encryption works

Your browser encrypts with AES-256-GCM. The key travels only in the part of the link after the `#`, which browsers never send to a server. Read the full design on the [security page](/security/).