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File Version Comparator

Upload two versions of the same file to compare their properties side by side. The File Version Comparator analyses file name, size, modification date, extension, and computes a SHA-256 cryptographic hash of the contents to definitively determine if the files are identical. Each attribute is clearly labelled as matching or different, giving you a complete picture of what changed between versions. All processing runs locally in your browser with zero uploads. Free, no signup required.

File Version Comparator

Upload two versions of the same file to compare their properties side by side. The tool analyses file name, size, modification date, extension, and computes a SHA-256 cryptographic hash of the contents to determine if the files are truly identical. All processing happens entirely in your browser - no uploads, no servers, complete privacy.

AFirst version (older/earlier)

Drop File A here or click to browse

Any file type supported

BSecond version (newer/later)

Drop File B here or click to browse

Any file type supported

Upload two file versions to compare their properties

Compares file name, size, modification date, extension, and SHA-256 content hash

Why Use Our File Version Comparator?

Side-by-Side Version Comparison

Upload two file versions and compare their properties instantly. The file version comparator shows every attribute - file name, size, extension, modification date, and cryptographic hash - in a clean side-by-side layout. Each field is clearly labeled as matching or different, making it easy to spot exactly what changed between versions.

SHA-256 Cryptographic Hash Verification

The tool computes a SHA-256 cryptographic hash for both files using the Web Crypto API. This hash serves as a digital fingerprint of the file contents - if the contents differ, even by a single byte, the hash will be completely different. This provides definitive proof of whether files are truly identical.

Comprehensive File Attribute Analysis

Beyond content hashing, the file version comparator analyzes five key attributes: file name, file size, file extension, last modified date, and content fingerprint. This comprehensive view helps identify whether changes were made to the content, metadata only, or both - giving you a complete picture of version differences.

100% Browser-Based & Private

All file processing happens entirely in your browser using the File API and Web Crypto API. Your files never leave your device - no uploads to any server, no third-party processing, no data stored in the cloud. Compare confidential documents, source code files, or sensitive data with complete privacy and security.

When to Compare File Versions

Source Code Version Verification

Compare two versions of a source code file to verify that the contents match after a refactor, merge, or automated transformation. The SHA-256 hash comparison provides definitive proof that the file contents are identical, even if metadata like modification dates differ.

Download Integrity Verification

After downloading a file from multiple sources or at different times, use the file version comparator to verify that the files are identical. Compare the content hashes to ensure no corruption, tampering, or partial download occurred during the transfer process.

Document Authenticity Checking

Compare an original document with a received copy to verify authenticity. If the content hashes match, you can be confident the file was not modified in transit. If only metadata changed but content matches, the file was likely resaved but not altered.

Backup Consistency Checking

Verify that backup copies of important files match the originals. Compare the original file against its backup to ensure the backup process is working correctly and the backed-up data is intact and unmodified.

Export & Conversion Validation

When converting or exporting files between formats, verify that the output accurately represents the input. While format conversions change the binary content, the file version comparator can verify that size and other attributes are within expected ranges.

Team Collaboration Auditing

Compare file versions during collaborative workflows to confirm that team members have submitted the correct updated files. The tool provides a quick way to check if expected changes were made and no unintended modifications occurred.

Understanding File Version Comparison

What Is File Version Comparison?

File version comparison is the process of analysing two files to determine whether they are the same version or different. The File Version Comparator examines multiple attributes - file name, size, extension, last modified date, and a SHA-256 cryptographic hash of the contents - to provide a comprehensive comparison. Unlike simple date-based checks, the cryptographic hash ensures that even a single byte difference in the file contents is reliably detected.

How the Comparison Engine Works

When you upload two files, the tool reads each file using the browser File API and computes a SHA-256 hash using the Web Crypto API. SHA-256 is a one-way cryptographic function that produces a unique 64-character hexadecimal string for each file. If the file contents differ in any way, the resulting hash will be completely different. Simultaneously, the tool extracts the file name, size, extension, and modification timestamp from the File object, then compares all five attributes field by field.

Understanding the Comparison Results

Each compared field receives a status: Identical (values match in both files), Different (values exist in both but differ), Only in A (field exists only in the first file), or Only in B (field exists only in the second file). The most critical field is the SHA-256 content hash - if this matches, the file contents are identical regardless of what metadata says. Conversely, if the hash differs but metadata matches, the file was modified after the metadata was last updated.

Browser-Based & Private by Design

All processing runs entirely in your browser using standard Web APIs. The File API reads files from your local filesystem without uploading them anywhere. The Web Crypto API computes SHA-256 hashes natively in the browser. No data is ever sent to a server, stored in the cloud, or processed by a third party. This zero-server architecture ensures complete data privacy, making the tool suitable for comparing confidential files, proprietary code, and sensitive documents.

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Frequently Asked Questions About File Version Comparator

What is a file version comparator?
A file version comparator is a tool that compares two files to determine if they are the same version. It analyses multiple attributes - file name, size, modification date, extension, and a SHA-256 cryptographic hash of the contents - and presents the results side by side with clear indicators for matching and differing fields. This helps verify whether files have been modified, corrupted, or are truly identical.
How does the SHA-256 content hash work?
SHA-256 is a cryptographic hash function that takes the complete contents of a file and produces a unique 64-character hexadecimal string. Even a single byte difference in the file contents produces a completely different hash value. The File Version Comparator uses the Web Crypto API built into modern browsers to compute these hashes locally, ensuring both accuracy and privacy. If two files have the same SHA-256 hash, their contents are mathematically guaranteed to be identical.
What attributes are compared between the two files?
The tool compares five key attributes: file name (the exact filename including extension), file extension (the .ext portion identifying the file type), file size (total bytes, displayed in human-readable format), last modified date (the filesystem timestamp of the last modification), and SHA-256 content hash (a cryptographic fingerprint of the binary contents). Each attribute is independently compared and labelled as identical or different.
Is my data safe when using this tool?
Absolutely. All processing happens entirely in your browser using standard Web APIs. The File API reads files from your local filesystem, and the Web Crypto API computes SHA-256 hashes natively. Your files are never uploaded to any server - they remain on your device throughout the entire process. This zero-server architecture ensures complete data privacy, making the tool suitable for comparing confidential documents, proprietary code, and sensitive personal files.
Can I compare files of different types?
Yes! The file version comparator supports any file type - images, documents, archives, audio, video, executables, source code, and more. The tool works with the binary contents of the files, so the file format does not matter. You can compare a Word document with a PDF, a PNG with a JPEG, or any other combination. However, files of different types will naturally have different names, extensions, and most importantly, different content hashes.
What does it mean if only the hash is different?
If the file name, size, extension, and modification date are all identical but the SHA-256 hash is different, this means the file contents have been modified. This can happen when a file is resaved (which may change embedded metadata like a save timestamp without changing the filename), when software modifies file contents during processing, or when the file has been tampered with. The hash difference is the most definitive indicator of content change.
What does it mean if the hash matches but metadata differs?
If two files have the same SHA-256 content hash but different metadata (such as modification date or filename), this typically means one file was copied or renamed without modifying the contents. The modification date may differ because copying a file to a new location updates the timestamp. The content hash matching confirms that no actual content changes were made, even though the metadata suggests a difference.
Is this file version comparator free?
Yes - 100% free, forever. No signup, no account creation, no premium tier, no usage limits, and no ads. Compare as many file pairs as you need, as often as you need. All processing is done locally in your browser with zero server involvement. We believe essential file comparison utilities should be freely available to everyone.