SHA3-512 File Checksum Calculator
Compute the SHA3-512 checksum of any file locally, even large ones, and compare it with the published hash to verify the download. Free and private.
No file selected yet. The checksum appears as soon as you pick a file.
The file is read in chunks inside your browser and is never uploaded.
What is SHA3-512 File Checksum?
This tool calculates the SHA3-512 checksum (512-bit digest) of a file you choose and compares it with an expected value. The file is read in 4 MB chunks inside your browser, so large files work and nothing is uploaded.
How to use SHA3-512 File Checksum
- Click the drop zone or drag a file onto it; the file is read in chunks and a progress bar is shown.
- Check the File name and File size shown below to make sure you picked the right file.
- Paste the checksum published by the provider into Expected checksum — you get Match or Mismatch (case,
0xand a trailing file name are ignored). - Choose the Output format if you need uppercase hex or Base64, then click Copy.
Example
A file named hash-abc.txt containing the 3 bytes "abc" (no newline)
b751850b1a57168a5693cd924b6b096e08f621827444f70d884f5d0240d2712e10e116e9192af3c91a7ec57647e3934057340b4cf408d5a56592f8274eec53f0
Pasting this value (in any case) into Expected checksum shows Match.
When to use SHA3-512 File Checksum
Use it to verify that a download, backup or copied file is intact when the publisher lists a SHA3-512 checksum, or to record a checksum before transferring a file. A match only proves integrity if you got the expected SHA3-512 from a trustworthy source (an HTTPS page or a signed file). To hash a short string instead of a file, use the SHA3-512 text hash generator.
How SHA3-512 File Checksum works
The file is sliced into 4 MB pieces with the File API and each piece is fed into an incremental SHA3-512 hasher, so memory use stays small and a progress bar can be shown. SHA3-512 is a sponge over the 1600-bit Keccak-f permutation (24 rounds of θ, ρ, π, χ and ι). The input is absorbed in 576-bit blocks (the rate; capacity 1024 bits), padded with the SHA-3 domain suffix 01 followed by pad10*1 (byte 0x06 … 0x80). After absorbing, the first 512 bits of the state are squeezed out as the digest. The suffix is the only difference from the original Keccak-512, but it changes every output. The comparison with the expected checksum is done on the bytes of the digest, so upper/lowercase hex and Base64 are both accepted.
Common Use Cases
- Verify an ISO, installer or firmware image against the checksum on the download page
- Confirm a file copied to a USB drive, NAS or cloud storage is bit-for-bit identical
- Record SHA3-512 checksums of release artifacts before publishing them
- Find out whether two files with different names have identical content
Security Note
A checksum only proves integrity if the expected value comes from a trusted channel; an attacker who can replace the file can usually replace a checksum shown next to it. The file never leaves your browser.
FAQs
Is my file uploaded to a server?
No. The file is read with the browser File API and hashed in JavaScript/WebAssembly on your device. You can disconnect from the internet after the page has loaded and it still works.
How large can the file be?
The file is processed in 4 MB chunks, so size is limited mainly by time, not memory. Multi-gigabyte files work; speed depends on your device.
My SHA3-512 does not match the published value. What now?
First make sure you compare the same algorithm and the same file (not a partially downloaded one). If the values still differ, download the file again from the official source; a persistent mismatch means the file is corrupted or not the one the publisher released.
What can I paste into Expected checksum?
The hex value in upper or lower case, with or without 0x, the Base64 form, or a whole line from a checksum file such as <hash> filename — only the first word is compared.