Method and privacy · 2026-09-07

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What this tool does

The selected CSV is decoded using your encoding and delimiter, preserving fields as text. It flags leading zeros, integer strings of 16 or more digits and scientific notation. Two files are compared by row and column position; their numbers are neither calculated nor rewritten.

Headers are included. Each result table shows up to 100 items; totals cover all parsed data. Outer quotes, BOM and record separators do not count as field changes. Spaces and line breaks inside fields are compared.

Supported scope

Each file is limited to 2 MiB, 20,000 rows and 200,000 cells. The decoded UTF-8 content also has a size limit, so some larger Big5 files may be rejected earlier. UTF-8/Big5 and comma, semicolon or tab are supported. Both files must use the same settings.

XLSX, UTF-16, inconsistent column counts, unclosed quotes and matching records by an identifier are unsupported. This is not data recovery or a complete quality certification. Unflagged fields may still have date conversion, decimal precision or other issues.

Data and privacy

File names and contents are processed only in this tab's memory. The tool neither uploads them nor saves them in persistent browser storage. Clear files and results removes the selections and results held by the page; reloading also clears them.

Ads are currently disabled. Analytics is off by default. Only Allow analytics loads Google Analytics to count page views and successful/failed checks, distinguishing samples/own files and single/pair checks. No file names, CSV text, differences, result tables or error messages are sent. Page URLs omit queries and referrers retain only the origin.

With consent, Google processes browser/device information, connection data and analytics cookie identifiers; this is not fully anonymous. Ad personalization and Google signals are disabled, and tool data is not used for ads. Analytics cookies last up to 60 days and your choice lasts 90 days. Use No analytics below any page to withdraw, stop future events and remove this site's analytics cookies. Tool functions remain available. Previously sent data is not automatically deleted from Google.

Hosting may still process ordinary connection logs, including IP addresses and page requests. See the Google Privacy Policy and Cloudflare Privacy Policy. This site cannot see or recover your selected files.

Original samples and sources

The sample is synthetic product data written for this tool, not real personal or business data. Guides link to Microsoft's original documentation and show review dates. This site is not affiliated with Microsoft.