Supported Paper Sizes
Werk24 supports automated processing for technical drawings up to a maximum size of A2. If a drawing exceeds this limit, the API returns a page size exception and the file is rejected.
For optimal results, ensure your drawings conform to the supported dimensions below and follow the best practices in this guide.
DO NOT SCALE DOWN IMAGE!
Scaling down will reduce readability and hurt feature extraction while not addressing the core constraint: the number of features on a page that can be handled reliably.
Acceptance Rules (Exactly How We Decide)
Werk24 infers the intended paper size from page geometry (borders, title block, frame marks) and does not rely solely on metadata. After normalizing orientation:
- ✅ Accepted if both dimensions are ≤ A2: short edge ≤ 420 mm and long edge ≤ 594 mm
- ❌ Rejected if either dimension exceeds A2 limits.
Practical equivalence: US sizes are accepted if their physical dimensions fall within A2 limits (see table).
Supported and Unsupported Paper Sizes
Werk24 supports A2 and smaller for automated processing. Larger than A2 will not be processed.
| DIN Size | Dimensions (mm) | Dimensions (inches) | Closest U.S. Size | Supported |
|---|---|---|---|---|
| A0 | 841 × 1189 | 33.1 × 46.8 | Larger than ANSI E | ❌ |
| A1 | 594 × 841 | 23.4 × 33.1 | ≈ ANSI D | ❌ |
| A2 | 420 × 594 | 16.5 × 23.4 | Between ANSI C/D | ✅ |
| A3 | 297 × 420 | 11.7 × 16.5 | ≈ ANSI B | ✅ |
| A4 | 210 × 297 | 8.3 × 11.7 | ≈ US Letter | ✅ |
As shown above, A2 and smaller are supported.
Why We Cap at A2
- Feature density & OCR stability: Very large sheets (A1/A0) often contain hundreds of callouts, tiny annotations, and dense leader networks that degrade precision/latency.
- Runtime predictability: Keeping page geometry within A2 bounds ensures consistent throughput for queueing, OCR, and geometry analysis.
Relation to DPI (Resolution)
Paper size and DPI are independent constraints:
- You must meet the paper size limit (≤ A2) and the resolution minimum (≥ 200 DPI).
- See: Resolution Limitations for Technical Drawings for minimum pixels per size and export tips.
Handy targets at 200 DPI (minimum): A4 ≈ 1654×2338, A3 ≈ 2338×3307, A2 ≈ 3307×4677. We recommend 300–400 DPI for best results.
Scaling, Plot Ratios & Common Pitfalls
- ❌ Printing A1 to A3 to “fit limits” does not fix feature density; it only shrinks text/symbols and often breaks OCR.
- ❌ “Fit to page” exports can distort intended scale and confuse size inference.
- ✅ Export at the intended paper size (no scaling) and keep within A2 if you need automated processing.
If your master is A1/A0: Split/retile into multiple A2 (or smaller) sheets logically (by view zone or assembly section). Keep consistent title blocks and references across sheets.
Vector PDFs vs. Raster Files
- Vector PDF is preferred. Page size is determined by the PDF page box and border geometry.
- Raster-only PDFs/Images: The paper size is inferred from border/title block proportions; resolution and size checks both apply.
- Hybrid PDFs: If export flattened vector to raster at large sizes, you may hit both the page size and DPI limits. Keep vector primitives whenever possible.
Multi-Sheet & Mixed Sizes
- Per-sheet evaluation: Each page is checked independently. A multi-page PDF with one A1 page will be rejected for that page.
- Best practice: Keep all sheets ≤ A2 and use consistent orientation, border thickness, and title block placement across the set.
FAQ
Q: Are US/ANSI sizes allowed? A: Yes, if the physical dimensions are ≤ A2 after orientation normalization.
Q: Can I just print my A1 at 50% onto A2? A: It may pass the size check, but text and symbols often become too small. Split into logical A2 sheets instead.
Q: Does the size limit change if my drawing is vector? A: No. Page size limits apply to both vector and raster. Vector just improves legibility.
Q: What about very long custom sheets (e.g., 297 × 1200 mm)? A: If any dimension exceeds 594 mm, it is rejected. Use multiple sheets.
Q: One page in my multi-page PDF is A1 — will the whole file be rejected? A: That page will be rejected. Best practice is to separate or fix the offending page(s).
Best-Practice Checklist
- [ ] Keep every sheet A2 or smaller (≤ 420 × 594 mm).
- [ ] Prefer vector PDF export from CAD; avoid “fit to page”.
- [ ] For large masters (A1/A0), tile into multiple A2/A3 with clear cross-refs.
- [ ] Pair with ≥ 300 DPI for raster content (see Resolution guide).
- [ ] Maintain full borders/title block (helps size inference).
- [ ] Use consistent layout, orientation, and title block across all sheets.
If you still encounter DRAWING_PAGE_SIZE_TOO_LARGE after following this guide, share a sample (redacted if needed) and the export settings. We’re happy to help you pick the best tiling/export strategy.