SamplePilot
SheetPair
DiffCheck.io
Diff Checker
Beyond Compare
WinMerge
SheetPair is a browser-based tool for comparing two CSV or Excel files. Upload both files, map the columns you want to match on, and instantly see what's matched, what's different, and what's missing.
How it works: Drop in two files, select your key columns, and SheetPair shows matched rows, rows with differences (highlighted cell by cell), and rows that only exist in one file. Results are ready in seconds, even with thousands of rows.
Privacy-first: All processing runs in your browser using Web Workers. Your files never leave your machine โ there's no upload endpoint and no server-side storage. Verify it yourself in DevTools.
Smart matching: Exact matching via hash-map lookup, Jaro-Winkler fuzzy matching for typos and formatting differences (e.g., "Jon Smith" vs "John Smith"), and numeric tolerance matching for rounding (e.g., $100.00 vs $99.99).
Built for: Accountants doing bank reconciliation, analysts comparing datasets, small businesses matching vendor lists or invoices, developers validating data migrations, and anyone tired of VLOOKUP across two spreadsheets.
Free tier: Compare up to 1,000 rows with 3 reconciliations per day. No signup required. Paid plans support up to unlimited rows with AI-powered features.
SamplePilot SheetPairSheetPair's answer:
Your data never leaves your browser. Unlike most comparison tools, SheetPair processes files entirely client-side using Web Workers. No uploads, no servers, no risk. It also supports fuzzy matching for typos and AI-powered column detection โ features you usually only find in enterprise tools.
SheetPair's answer:
Most file comparison tools (Beyond Compare, Diffchecker) compare lines of text. SheetPair understands rows and columns โ it matches records across two files, highlights differences per field, and shows what's missing from each side. It's purpose-built for data reconciliation, not generic diffing. Plus it's free to start with no signup required.
SheetPair's answer:
Next.js, TypeScript, Tailwind CSS, Cloudflare Workers, Supabase, and Claude AI (Anthropic). File parsing and matching run in browser Web Workers for speed and privacy.
SheetPair's answer:
Accountants, finance teams, data analysts, and operations managers who regularly need to compare spreadsheets โ bank reconciliations, invoice matching, inventory audits, or migrating data between systems. Anyone who's tired of doing VLOOKUP across two files.
SheetPair's answer:
I kept seeing people struggle with comparing two spreadsheets โ writing complex VLOOKUP formulas, copy-pasting between files, or paying for clunky enterprise software. I built SheetPair to make it as simple as uploading two files and clicking a button. Privacy was a priority from day one โ your data stays in your browser.