What it means
The code runs in your browser. Your document stays in the tab's memory and is saved straight to your device.
How to check
Load a tool, switch your device offline, and run it. On-device tools keep working.
Tools that need a server
A few tools need a server. They are marked “server” and say so before you start.
Good to know
Each tool page states whether it runs on your device or needs a server. Server tools say how long files are kept.
Questions
Does it work offline?
Once loaded, on-device tools can keep working without a connection.
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