HASH & CHECKSUM
Verify a download without uploading it
Compute MD5, SHA-1, SHA-256, SHA-512, BLAKE3 or CRC32 for a file and compare it against a published checksum. Files are read in chunks, so a multi-gigabyte ISO hashes without ever being held in memory — and nothing is sent anywhere.
Paste the whole line if you like — a file name, extra spaces, upper case and the SHA256 (file) = … form are all understood. Only the digest is read.
What a matching checksum does and does not tell you
A match means the file you have is byte-for-byte the file whose checksum was published. It does not mean the file is safe — if the page that published the checksum was compromised, the checksum was published by whoever compromised it. A checksum verifies integrity, not trust.
MD5 and SHA-1 are both broken against a determined attacker: a deliberate collision is practical, so a match proves the file was not corrupted in transit, not that nobody chose those bytes on purpose. Use SHA-256 where the publisher offers it. CRC32 is not a hash at all — it is an error check, and forging one takes seconds.