File Hash Checker enables you to compute highly secure cryptographic checksums (MD5, SHA-1, SHA-256, SHA-512) for any file directly inside your browser. Because the hashing algorithm utilizes the HTML5 FileReader API, your files are processed entirely on your local machine and are NEVER uploaded to a server. Safely verify OS ISO images, software binaries, sensitive documents, and ZIP archives against official checksums to ensure they have not been tampered with or corrupted during download.
A file hash acts as a unique digital fingerprint. Even modifying a single pixel in an image or a single bit in a 5GB file will drastically alter the resulting hash string. By comparing the hash of the file you have on your hard drive with the hash published by the software creator, you mathematically guarantee the file is identical and free from corruption or hacking.
NO. This is critically important: your file NEVER leaves your computer. We use local JavaScript APIs (FileReader/SubtleCrypto) to calculate the hash locally using your CPU. It is completely safe for confidential documents.
Because the file is streamed and processed entirely in your RAM/Browser, the limit depends on your device's available memory. Most modern browsers comfortably handle files up to 1GB or 2GB without issue.
Only use MD5 or SHA-1 if you are comparing against legacy checksums. For maximum modern security (verifying against tampering), always use SHA-256 or SHA-512.
Hashing requires the CPU to process every single byte of the file. A 1GB file takes a few seconds longer than a 1MB file because the algorithm must sequentially compute billions of bytes.
No. Cryptographic hashes are strictly one-way functions. It is impossible to recreate the original file from the hash.
Yes, it is entirely free, requires no login, and imposes no paywalls.
Tool workspace
Free File Hash Checker online — instantly verify file integrity directly in your browser. Calculate MD5, SHA-1, SHA-256, and SHA-512 checksums without uploading your file. 100% private.
Input
Select ubuntu-22.04-desktop-amd64.iso | Algorithm: SHA-256
Output
a435f6f393dda581172... (matches official Ubuntu release hash)
