Private Checksum Verifier

Verify everything.

SHA-256. On-device. Instantly.

Drop any file to verify

or

No upload
Works offline
No tracking

Need checksum verification offline? The offline bundle verifies any file without internet. $49 once.

Get Bundle →
// How it works

Three steps. Zero uploads.

01
Drop
Drop your file into fwip.
02
Hash
MD5, SHA-1, and SHA-256 checksums are calculated locally in your browser.
03
Verify
Compare the hash against the expected value. Match means the file is intact and unmodified.
// Why this is different

Verify files without uploading them.

Most online checksum tools upload your file to a server to calculate the hash. fwip calculates checksums entirely in your browser. Your file never leaves your device.

fwip works differently. The processing engine runs entirely in your browser. Your file is read from your device, processed on your CPU, and the result is saved back to your device. No server is involved. We literally cannot see your file.

No server processing

Everything runs on your device using WebAssembly. Your file never touches a network.

No account required

Drop a file. Get a result. No sign-up, no email, no password.

No subscription

Free in the browser. $99 once for the offline bundle. That's it. Forever.

Works offline

The desktop version works with no internet connection at all.

Use it free in your browser. Own it offline for $15. No subscription. Verify anything.
// How fwip compares

fwip vs the rest.

fwipOnlineMD5.comFileCheck.meHashCalc (desktop)
Upload requiredNoNoYesN/A
Account requiredNoNoNoNo
Price$15 / toolFreeFreeFree
Files leave deviceNeverNo (client-side)YesNo
Works offlineYesNoNoYes
Batch processingOffline bundleNoNoYes
// Questions

Frequently asked.

What is a checksum?▾
A checksum is a fixed-length string (hash) calculated from a file's contents. If even one byte changes, the checksum changes. Comparing checksums verifies that a file hasn't been corrupted or tampered with.
How do I verify a file's checksum?▾
Drop your file into fwip. It calculates MD5, SHA-1, and SHA-256 hashes instantly. Paste the expected hash (usually provided by the file's publisher) to compare.
Is my file uploaded?▾
No. The hash calculation runs entirely in your browser using the Web Crypto API. Your file never leaves your device.
Which algorithm should I use?▾
SHA-256 is the most secure and widely used. MD5 and SHA-1 are provided for compatibility but are considered less secure for cryptographic purposes.
When would I need to verify a checksum?▾
After downloading software, firmware, ISO images, or large files. Verifying the checksum confirms the download wasn't corrupted during transfer or tampered with.
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Offline. No browser. No internet. No excuses.
$15
This tool
  • Checksum Verifier · offline
  • Batch processing
  • No file size limit
  • 3 devices · one payment
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Complete suite
  • All 200+ tools · offline
  • No file size limit
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One-time payment · 3 devices · Updates included · Mac + Windows + Linux