SHA256 OnlineCheck an archived installer
Use the historical SHA1 reference for that exact build, platform and filename.
Legacy SHA compatibility · Files
SHA1 File Checksum
Calculate SHA1 for one or many files. Verify a GNU or BSD checksum list without uploading files.
Input No upload
or drop files here · up to 100 · 2 GiB eachFiles stay on this device.
Output Your result · SHA1
Ready to calculate
0 / 0 bytes processed
Browser-local hashing. Inputs masked in Clarity.
No account. No uploads. Just your browser.
SHA1 versus SHA256
| Algorithm | What differs |
|---|---|
| SHA1 | 160-bit SHA-1 output; broken collision resistance. |
| SHA256 | 256-bit SHA-2 output; a different algorithm and digest length. |
Verify SHA1 files in three steps
- 1
Select the actual files
Choose up to 100 files, each at most 2 GiB. The file contents are read locally.
- 2
Read the calculated checksum
SHA1 returns 40 lowercase hex characters. Copy digest preserves the whole output.
- 3
Compare a trusted release list
Read a local manifest or paste a trusted expected value. Review each filename and any missing entries.
SHA1 file workflows
Maintain an older checksum workflow
Reproduce SHA1 where an existing system requires it, without treating it as modern collision-resistant authentication.
Reconcile a release folder
Verify the supported SHA1 list and inspect missing or unlisted files separately.
Details that affect your SHA1 result
How SHA1 works
SHA1 produces a 160-bit result: 40 hexadecimal characters. It remains useful for reproducing legacy fingerprints, but its collision resistance is broken. Prefer SHA256 for new integrity workflows.
A SHA1 file checksum describes raw bytes, not the extracted content of an archive. Recompressing the same documents changes the archive checksum. Use the publisher’s original file and the SHA1 algorithm.
Verify SHA1 files
Choose or drop files and calculation starts automatically. Each file is read sequentially in 2 MiB chunks inside a background worker. Up to 100 files and 2 GiB per file are accepted. Cancel terminates the active worker.
Paste a trusted expected digest to compare directly. With no expected value, Not compared yet is not a verification success. Every batch row includes the complete digest, byte count and comparison outcome.
Read a SHA1 checksum manifest
Open manifest options to read a local list or paste GNU digest–filename lines or BSD ALGORITHM (filename) = digest lines. Verify selected files runs the comparison again with the list. The filename is matched exactly, including spaces and relative folders.
Duplicate names, invalid digest lengths, mixed algorithms and unsupported lines block manifest verification. Missing files and files not listed are displayed; no basename-only guessing or silent success is used. Lists are limited to 1 MiB and 100 entries.
Private file handling and practical limits
Hashing runs in browser memory with no upload endpoint. Microsoft Clarity runs on this page, with the entire tool workspace masked, including filenames, digests and manifests. Google Analytics runs only on the four information pages. A local report can be copied or downloaded. See Privacy for details.
The 2 GiB ceiling is not a promise about every phone. If a device struggles, cancel and use a system checksum utility. A matching value proves only equality with the reference digest, not safety or publisher identity.
Known SHA1 result: empty input
SHA1 · 0 bytes · no HMAC. Empty input is not the same as no file selected.
da39a3ee5e6b4b0d3255bfef95601890afd80709SHA1 file checksum FAQ
Why is my SHA1 reference 40 hexadecimal characters?
SHA-1 produces 160 bits, represented by 40 hex characters. A 64-character reference is not a full SHA1 reference for this comparison field.
Can SHA1 certify that two files are identical?
A matching value confirms this checksum comparison, not a mathematical guarantee of unique content. SHA-1 collision resistance is broken; it is unsuitable for adversarial authenticity checks.
Can I load an old SHA1SUMS list?
Yes, if its lines use supported GNU digest-plus-filename or BSD algorithm-plus-filename syntax. Exact names and the SHA1 algorithm are required.
Does switching SHA1 to SHA256 convert the reference?
No. Each digest must be computed from the original file bytes. A SHA256 value cannot be derived by relabeling or padding a SHA1 value.
What happens after selecting files for SHA1?
Files are hashed automatically and sequentially. The result says calculated until an expected digest is supplied; Match or Mismatch describes a comparison, not just a completed calculation.
How should I prepare a SHA1 checksum manifest?
Use GNU digest followed by a filename, or a BSD algorithm (filename) = digest line. Each SHA1 reference needs 40 hex characters. Malformed lines and duplicate names block verification.
Why is a file missing from my SHA1 batch?
Names must match exactly, including spaces and relative paths. A selected file not in the manifest is reported separately and is not silently treated as a verified match.
Can I export my SHA1 batch results?
Download report saves a local text report with filenames, byte counts, digests and comparison states. Keep that report private if its filenames or checksums are sensitive. No report is uploaded.