SheetDiff is a schema-agnostic Google Sheets add-on for spreadsheet comparison, structural diffing, duplicate detection, and QA reporting — directly inside Google Sheets.
Designed for localization, transcription QA, financial reconciliation, data auditing, and spreadsheet review workflows, SheetDiff analyzes changes between sheets and generates professional, color-coded reports in seconds.
=== COMPARISON MODES ===
🔍 STRUCTURAL DIFF
Compare an original snapshot against an edited version with advanced change detection:
• Unchanged, Modified, Added, Deleted rows
• Split and Merge detection
• Inline text highlighting (green additions / red removals)
• Simple Mode for lightweight diffs
• Positional Mode for strict row-by-row comparison
• Unified Output across multiple sheets
• Batch Comparison support
📊 CELL-BY-CELL COMPARISON
Audit sheets at cell level:
• Exact, Normalized, and Fuzzy comparison modes
• Positional, Key-based, or Content-based row alignment
• Header-aware column matching even when order differs
• Compare formulas, notes, and data validation rules
• Per-sheet statistics and aggregate scoring
• Multi-sheet comparison support
🔎 DUPLICATE FINDER
Detect duplicates within or across sheets:
• Self-compare or cross-sheet duplicate detection
• Composite key matching
• Column-specific duplicate scans
• Positional cell-level duplicate detection
• Color-coded duplicate reports
• One-click duplicate merge/removal with undo snapshots
=== KEY FEATURES ===
✅ Schema-agnostic — works with any spreadsheet layout
✅ Auto-detect speaker, timestamp, transcript, and event columns
✅ Visual color-coded Diff Viewer with inline changes
✅ 9 QA metrics including CER, WER, SER, SegER, SACR, and Composite Quality Score
✅ Exportable QA reports for audits and reviews
✅ Snapshot workflow for version tracking
✅ Saved comparison scenarios and presets
✅ Custom regex/text transform rules per comparison mode
✅ Ignore specific columns during comparisons
✅ Cross-spreadsheet import from Google Drive
✅ Compare Picker with runtime estimation and sheet previews
✅ Chunked execution with progress tracking and resume support
✅ Unicode normalization across multiple numeral systems
✅ Optional accent/diacritics-insensitive comparison
✅ Optimized rendering for large datasets
✅ Automatic backup snapshots for undo support
✅ Fully configurable thresholds, mappings, visibility rules, and comparison behaviors
=== USE CASES ===
• Localization and transcript QA
• Translation review and post-editing
• Spreadsheet auditing and reconciliation
• Financial report comparison
• Duplicate detection and cleanup
• Formula and metadata validation
• Deliverable version tracking
• General spreadsheet change analysis
=== GETTING STARTED ===
1. Install the add-on
2. Open Google Sheets → Extensions → SheetDiff
3. Configure comparison settings
4. Commit a snapshot (optional for Structural Diff)
5. Run comparison and select sheets
6. Review results and export reports
