Download verify
Confirming a download wasn't corrupted
Many open-source projects publish SHA-256 checksums alongside downloads. Hash your downloaded file, compare to published value — if they match, file is intact and unaltered.
Generate MD5, SHA-1, SHA-256, SHA-512 hashes for any file. Verify integrity of downloads or delivered files.
What this does
Drop a file in, get all four hash values instantly. Useful for verifying downloads (does my file match the published checksum?), confirming file integrity after transfer, deduplicating large file sets, or generating evidence-tracking values for legal chain-of-custody. Runs entirely in your browser using Web Crypto API + a local MD5 implementation.
Any file type, any size up to a few GB. The page reads the file into memory and starts hashing.
MD5 first (fastest), then SHA-1, SHA-256, SHA-512 in order. For a 100 MB file, all four finish in a couple seconds on modern hardware.
Each hash has a Copy button. Paste into your downloads-verification page, your chain-of-custody log, or your deduplication script.
Download verify
Many open-source projects publish SHA-256 checksums alongside downloads. Hash your downloaded file, compare to published value — if they match, file is intact and unaltered.
Forensics
Legal evidence (logs, photos, documents) needs hash values recorded at each handoff to prove no tampering. SHA-256 is the most commonly required for court submissions.
Dedupe
Hashing 1,000 photos to find duplicates is faster than visually comparing them. Same hash = same file, regardless of name or path.
Backup verify
Hash file before backup, hash again after restore. Match = backup worked, file integrity preserved.
Software dev
Package managers use file hashes to verify downloaded dependencies match expected versions. Useful for security audits of supply chain.
Security
VirusTotal and other security services accept SHA-256 lookups. Hash a suspicious file, check if it's a known malware variant before opening.
MD5 (128-bit)
Best for: Quick dedup, file-id mapping. Fast. NOT for security.
Watch out: Cryptographically broken since 2004 — collisions can be engineered. Don't use for verifying authenticity.
SHA-1 (160-bit)
Best for: Git commit IDs, legacy chain-of-custody. Moderately fast.
Watch out: Also broken (collisions demonstrated 2017). Migrate to SHA-256 for new use.
SHA-256 (256-bit)
Best for: Most modern use cases — downloads verification, evidence, certificates. Safe.
Watch out: Slightly slower than MD5/SHA-1 but still very fast. Use this by default.
SHA-512 (512-bit)
Best for: Long-term archival, high-security contexts. Future-proof.
Watch out: Roughly same speed as SHA-256 on 64-bit hardware. Use when paranoid; SHA-256 is usually enough.
If you hash the same file twice and get different values, the file is being modified between hashes (e.g., a log file being written to). Hash a copy in a frozen state.
Most published checksums use hex (lowercase, 64 chars for SHA-256). Some Git/HTTP headers use base64. They represent the same hash — just different encodings.
If you're hashing text files (config, source code), Windows CRLF vs Unix LF line endings produce different hashes. Normalize line endings first or hash the binary contents.
Above ~1 GB, browser memory becomes the bottleneck. Use a CLI tool (`shasum`, `sha256sum`) for hashing huge files.
Everything runs locally in this tab. Nothing uploads, nothing stores on a server, nothing indexes.
No progress bars stuck at 99%, no rate limits, no 'please wait' screens. Drop, click, done.
When the free tool isn't enough, deliver from files.your-agency.com — password and view analytics included.
Eliminates manual zipping steps when sending multiple files to clients.
Lets users actually compress files right away instead of guessing output ranges.
Saves time and reduces confusion in client handoffs by standardizing delivery messages.
Helps users send oversized PDFs that fail email and portal upload limits.
Most PDF merge tools upload your sensitive documents to a server. Ours never does — everything happens in your browser with pdf-lib.
Extracting pages from a PDF usually requires uploading to a third party. This tool does it locally in your browser.
No. Hashing happens in your browser using the Web Crypto API (window.crypto.subtle). The file never leaves your device.
SHA-256 for most modern use cases (security, integrity verification). MD5 is faster but cryptographically broken — only use for non-security uses like deduplication. SHA-1 is also broken; use SHA-256 or SHA-512 instead.
Limited by browser memory. Most browsers handle 1-2GB files comfortably for hashing (it's a streaming operation, not loading the whole file into memory).
Modern browsers with Web Crypto API are typically 60-80% of native command-line speed (e.g., `sha256sum`). For a 1GB file: ~5-10 seconds in browser, ~3-5 seconds command line.
Yes. Many software downloads publish their SHA-256 hash. Hash your downloaded file with this tool and compare to the published hash — they should match exactly.