How to use: Swap case

Swap case is a free online Text Tools tool that converts uppercase letters to lowercase ones, and lowercase ones to uppercase ones instantly in your browser. Paste your data, adjust the options and get the result in real time — no installation, no sign-up, and nothing is ever uploaded to a server.

Use Swap case now →

Description

Converts uppercase letters to lowercase ones, and lowercase ones to uppercase ones.

Text Tools
Because everything is computed client-side, Swap case is safe to use with sensitive data such as API keys, tokens or private logs.

Swap case — Input → Output

How to use

Using Swap case takes three steps:

Paste your data into the input box (or load the example).
Configure the options to match your target format or scenario.
Copy, download or inspect the output — it updates live as you type.

How to use

Run

Use cases

Common situations where Swap case helps:

Converts uppercase letters to lowercase ones, and lowercase ones to uppercase ones.

Parameters

This tool has no options — it works on the input alone.

FAQ

What is Swap case?

Swap case converts uppercase letters to lowercase ones, and lowercase ones to uppercase ones. It runs entirely in your browser, so your data stays private.

Is Swap case free to use?

Yes. Swap case is free, unlimited and works without registration or installation.

Does my data get uploaded?

No. All processing happens locally in your browser; nothing is sent to any server.

Good to know

Everything runs client-side, so extremely large inputs are limited by your browser tab’s memory rather than by a server upload limit.
The worked example below could not be pre-computed for this tool (threw: function is not iterable (cannot read property Symbol(Symbol.iterator))); the interactive tool above still works normally.

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