Calculate and compare MD5, SHA-1, SHA-256 & SHA-512
A file checksum calculator produces a fixed-length digest from a file's exact bytes. Select a local file, calculate four common checksums, then compare the complete value published by a source you trust. The file is read in this browser tab and is not uploaded to InstaHasher.
Drag & drop a file here
or click to browse
The whole file is read into browser memory and is not uploaded. Very large files may exceed the memory available on your device.
Paste an expected checksum below to compare it against the calculated values.
A matching digest means your file produced the same value with the same algorithm. It does not independently prove who published the file. Obtain the expected checksum from the publisher's trusted HTTPS page, signed release metadata, or another independent channel. If an attacker can replace both the download and the expected checksum, the values can still match.
| Algorithm | Digest | Hex characters | Guidance |
|---|---|---|---|
| MD5 | 128 bits | 32 | Legacy change detection only; collision resistance is broken. |
| SHA-1 | 160 bits | 40 | Legacy compatibility; avoid for adversarial verification. |
| SHA-256 | 256 bits | 64 | Practical default when publishing a new checksum. |
| SHA-512 | 512 bits | 128 | Use when the publisher supplies SHA-512 or your workflow requires it. |
On Windows PowerShell, run Get-FileHash .\filename.iso -Algorithm SHA256. On Linux with GNU Coreutils, run sha256sum filename.iso. Compare the output with the publisher's complete SHA-256 value.
The browser version uses Web Crypto for SHA-1, SHA-256 and SHA-512, and the locally served CryptoJS library for MD5. Web Crypto's digest method does not stream: this implementation loads the entire file into memory before calculating each digest.
Need to hash text? Use the online hash generator. For algorithm background, read what hashing means or the MD5 versus SHA-256 comparison.
Algorithm sizes and SHA guidance were checked against the NIST Secure Hash Standard. MD5 guidance follows IETF RFC 6151. Browser memory behavior follows MDN's SubtleCrypto digest documentation. Command examples were checked against Microsoft Get-FileHash and the GNU Coreutils manual. Last reviewed: .
A file checksum is a fixed-length digest calculated from the file's exact bytes. The same bytes and algorithm produce the same digest. A different result shows that the compared bytes differ, but a checksum is useful evidence only when the expected value comes from a source you trust.
Get the expected checksum and algorithm from the publisher's trusted HTTPS page or signed release information. Select the downloaded file here, calculate its checksums, paste the complete expected value, and compare. A match means the local file bytes produced that digest with the same algorithm.
Not by itself. A match links the file to the expected checksum, so trust depends on where that expected value came from. If an attacker can replace both the file and checksum, the comparison can still match. Use a trusted independent channel or verify a digital signature when authenticity matters.
No. The selected file is read in this browser tab. SHA-1, SHA-256 and SHA-512 use the browser's Web Crypto API; MD5 uses the locally served CryptoJS library. The implementation reads the whole file into browser memory, so very large files can fail on memory-limited devices.
Use the same algorithm as the published checksum. For a new workflow, SHA-256 is a practical interoperable default. MD5 and SHA-1 can detect accidental changes in legacy workflows, but Microsoft and the IETF advise against using them where protection from deliberate tampering is required.