Find Which Sheets Actually Changed
Upload two versions of your drawing set and instantly see added, removed, and modified sheets with AI-powered visual analysis.
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The PDF Comparison Tool helps AEC professionals quickly identify changes between two versions of a drawing set. Instead of manually comparing sheets one by one, upload both PDF versions and get an instant breakdown of what changed.
Our AI-powered analysis goes beyond simple file comparison—it examines each drawing to identify meaningful visual changes like new walls, moved equipment, updated dimensions, or modified annotations. Filter results by change type, export comparison reports to CSV, and visually compare drawings side-by-side, with an overlay view, or with pixel-level diff highlighting.
Perfect for reviewing revisions from consultants, tracking design changes between phases, or verifying contractor submittals match the latest issued set.
Features
Everything you need
- Compare two PDF drawing sets instantly
- AI-powered visual analysis of drawing changes
- Identify added, removed, modified, and unchanged sheets
- Side-by-side, overlay, and pixel diff view modes
- Export comparison report to CSV
- Filter results by change type
- Progressive PDF parsing with live progress
- Automatic sheet number and metadata extraction
How it works
Simple workflow
- 1Upload your old (previous) PDF drawing set
- 2Upload your new (current) PDF drawing set
- 3Click Compare Drawing Sets to start analysis
- 4Review the results table showing all changes
- 5Click any sheet to compare visually
- 6Export report for documentation
Use cases
Built for real-world scenarios
Revision Tracking
Quickly identify what changed between design development and construction documents phases.
Consultant Coordination
Compare consultant submittals to previous versions to verify requested changes were incorporated.
Quality Control
Ensure contractor RFI responses match the latest issued drawing set.
Change Documentation
Generate change logs for project records and client communication.
FAQ
Frequently asked questions
The tool first extracts metadata from each PDF page (sheet number, title, revision) to match sheets between versions. Then for modified sheets, AI vision analysis compares the actual drawings to identify meaningful visual changes.
The tool detects added sheets, removed sheets, and modified sheets. For modifications, it identifies both metadata changes (title, revision, scale) and visual changes (new elements, moved items, dimensional changes).
The tool supports PDF files up to 100MB. Large drawing sets with many pages will process progressively with live progress updates.
Your PDF files are processed locally in your browser for initial parsing. Only individual page images are sent to the AI for analysis—full documents are never uploaded to our servers.
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We're always looking to improve our calculators. If you have ideas for new features, improvements, or found something that could work better, we'd love to hear from you.
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