File checksum
Calculate SHA-256 or SHA-512 and compare a file against an expected checksum. Use File checksum locally with practical instructions, output settings and format limits.
File checksum
Calculate a SHA-256 or SHA-512 checksum for a file and optionally compare it with an expected hexadecimal value. Download a JSON report containing the algorithm, byte count, checksum and match status when supplied. Use it to compare file bytes across a handoff, while obtaining expected checksums from a source you trust.
- Compare a download with a published checksum
- Check whether two copies contain identical bytes
- Record a file checksum for a handoff
How to use File checksum
Choose the file to hash
Upload the exact file whose bytes you want to check. A checksum covers the full file representation, so use the final copy rather than an earlier draft.
Select the hashing algorithm
Choose SHA-256 or SHA-512 to match the expected checksum’s algorithm. Different algorithms produce different digest lengths and cannot be compared directly with one another.
Add an expected value if available
Paste only the expected hexadecimal checksum, or leave it blank to calculate one. Run Create result to hash the file and perform the optional comparison.
Read the verification report
Download the JSON and review the checksum, byte count and matches field when present. Investigate mismatches before assuming the selected file is the expected version.
Understand the settings
- Algorithm
- Choose algorithm according to the result you need. Available choices: SHA-256; SHA-512. The initial selection is SHA-256.
- Expected checksum (optional)
- Expected checksum (optional) is applied to this tool job. Use the value or syntax described in the example below. Leave it blank only when the field is described as optional.
Checking a supplied package
A package arrives with a separately published SHA-256 value. Upload the package, choose SHA-256 and paste the expected hexadecimal digest. Review the report’s match status and file byte count before treating the package as the same bytes described by that expected value.
Check your result
Choose a file or enter text where available. Review the settings, create your result and download the new copy. Processing stays on this computer. Input and expansion limits apply; originals are never overwritten. Open the saved output in the app or workflow where you plan to use it. Check one representative result before repeating the same settings with more files. The original files stay unchanged.
What to know before you start
- Files are processed on this device. Browser memory and engine-specific limits apply. Save results before reloading.
- Processing stays on this computer. Input and expansion limits apply; originals are never overwritten.
- Upload one file with a combined size of at most 100 MB. The completed output must fit within 200 MB.
- Files are checked by the local engine; a matching filename alone is not proof of valid contents.
- Selections and completed jobs stay available while you navigate inside this tab. Use My files to revisit results. Reloading or closing the tab clears the workspace; download results you want to keep first.
File checksum: common questions
What does a matching checksum establish?
A match indicates that the calculated digest equals the supplied expected value for the chosen algorithm. Its usefulness depends on trusting that expected value; the calculation alone does not identify who created the file or whether its contents are appropriate.
Why do visually identical PDFs have different checksums?
Checksums cover every file byte, including metadata, internal ordering and encoding details. Two documents can render similarly yet have different bytes, so a mismatch does not by itself identify which visible content changed between them.
What expected-checksum format is accepted?
Use a hexadecimal digest of the correct length for SHA-256 or SHA-512. The comparison ignores letter case and surrounding whitespace, but filenames, algorithm labels or other text from a checksum listing should not be included.
Can a checksum find a corrupted location?
No. The result tells you whether the complete digest matches an expected value; it does not locate the changed byte or repair a file. Obtain another trusted copy or use an appropriate comparison workflow to investigate a mismatch.
Does File checksum upload files to another service?
Processing runs in this browser, on your device. Files and pasted input are not uploaded to a conversion server. The website and required engine assets must load first; large operations depend on available device memory.
Can I continue after changing pages?
Selections and completed jobs stay available while you navigate inside this tab. Use My files to revisit results. Reloading or closing the tab clears the workspace; download results you want to keep first.