Font Size Detector
Calibrate with a known reference or run live page analysis to get pixel-perfect typographic scale for developers and designers.
Upload image / PDF
Drop your image here or click to upload
Supports JPG, PNG, WebP, GIF, PDF • Max 10MB (25MB for PDF)
We couldn't identify a font in that image
Try selecting a word or checking the letters below — we'll retry with a tighter crop.
Which word?
Select a word to retry with a tighter crop. We detected these from your image.
We couldn't auto-detect words. Use manual crop or type the text below.
If the crop is still blurry, type what you see.
We couldn't confidently identify this font.
Try another crop, different text, or a clearer image.
Original image
Crop manually
Drag to adjust. We'll use this tighter crop to retry.
Tip: crop tightly to 1–2 lines of text, high contrast.
✓ Runs locally in your browser — nothing uploaded
Or paste HTML/CSS directly — works for private pages.
Live Preview
Results will appear here
This is the extensible result shell. Future AI/API integration will populate:
- ● Match + confidence %
- ● Family, weight, style, category
- ● License / source (free, Google, Adobe)
- ● Live preview with your text
- ● Similar / alternative fonts
- ● Next actions: download, buy, test, copy CSS
Architecture ready for pluggable AI providers — UI not coupled to a single API. Swap provider via env.
How it works
Provide reference
Upload image with known height or set scale.
Measure
We compute cap-height → font size mapping.
Export
Copy CSS with fluid scale.
FAQ
Accuracy?
Within ~5% from high-res images; exact from live DOM.
Privacy note
Heavy image/PDF processing stays in your browser when possible. No fonts or files stored.