File checksum

This tool reads file bytes into the Web Crypto digest API and returns a lowercase hexadecimal checksum. The complete operation runs in temporary browser memory, so the input is never uploaded or stored by LocalKit.

Local processing
Local processing
Ready — nothing leaves this page
Input

The selected file stays inside this browser tab.

No file selected
Settings
Run tool

Browser memory only. No upload fallback.

Result
Your result will appear here

The input stays available if you need to adjust a setting.

How to use file checksum

  1. 1

    Add the source values or files shown in the workbench.

  2. 2

    Choose the settings for file checksum.

  3. 3

    Run the tool, inspect the local result, then copy or download it.

A realistic example

Generate a SHA-256 hash and compare it with a publisher's checksum before opening a download. The source and generated result remain in this browser tab throughout the operation.

Supported formats and limits

Input: any local file. Output: hexadecimal digest.

  • A matching checksum verifies bytes, not whether the publisher itself is trustworthy.
  • Available memory and browser limits still apply to very large inputs.

Questions people ask

What does file checksum change?

This tool reads file bytes into the Web Crypto digest API and returns a lowercase hexadecimal checksum.

Is any input sent to a server?

No. LocalKit performs this operation in your current browser tab.