Developer Tools
File Checksum Verifier — SHA-256, SHA-512 Hash in Your Browser
Compute SHA-256, SHA-512, or SHA-1 checksums for any file, entirely in your browser. Paste an expected hash to instantly verify whether your download matches the publisher's checksum. Your file is read into browser memory via the Web Crypto API — nothing is uploaded.
How to use this tool
- Select SHA-256, SHA-512, or SHA-1, then choose your file.
- The hash is computed instantly in your browser using the Web Crypto API.
- Paste the expected checksum to verify a match — a green result confirms the file is intact.
Frequently Asked Questions
- Is my file uploaded to a server?
- No. The browser reads the file into memory using the FileReader API and computes the hash with SubtleCrypto (crypto.subtle.digest). Nothing leaves your device.
- Why is SHA-256 the recommended algorithm?
- SHA-256 is the current industry standard for file verification. SHA-1 is deprecated (collision attacks found in 2017) and should only be used when the publisher provides no other option. SHA-512 is slower but offers a larger output for high-security use cases.
- What does a checksum mismatch mean?
- A mismatch means the file you downloaded is different from the file the publisher signed. This can indicate: a corrupted download (retry the download), a man-in-the-middle attack, or a compromised mirror. Treat a mismatch as a serious warning and do not execute the file.
- How do I find the expected checksum?
- Software publishers typically post checksums on their official download page alongside download links. Common filenames are SHA256SUMS, checksums.txt, or a file with a .sha256 extension. Always download the checksum from the official source — not from the same mirror as the file.
How to Verify a File Checksum in Your Browser (2026)
Verify SHA-256 or SHA-512 checksums for downloaded files entirely in your browser. Confirm file integrity without uploading — the Web Crypto API computes hashes locally.