We Now Support A1 Drawings
We are happy to announce that Werk24's automated processing now supports technical drawings up to A1 (594 × 841 mm) — up from the previous A2 limit. That effectively doubles the sheet area we can ingest without you having to retile or split your masters.
What changed
Until now, the largest sheet we accepted for automated feature extraction was A2 (420 × 594 mm). Anything larger triggered a page-size exception (DRAWING_PAGE_SIZE_TOO_LARGE) and was rejected.
Starting today, the acceptance rule moves up one full ISO 216 step:
| DIN Size | Dimensions (mm) | Closest U.S. Size | Before | Now |
|---|---|---|---|---|
| A0 | 841 × 1189 | Larger than ANSI E | ❌ | ❌ |
| A1 | 594 × 841 | ≈ ANSI D | ❌ | ✅ |
| A2 | 420 × 594 | Between ANSI C/D | ✅ | ✅ |
| A3 | 297 × 420 | ≈ ANSI B | ✅ | ✅ |
| A4 | 210 × 297 | ≈ US Letter | ✅ | ✅ |
A drawing is now accepted when both dimensions are within A1 limits after orientation normalization:
- short edge ≤ 594 mm and long edge ≤ 841 mm
US/ANSI sizes are accepted whenever their physical dimensions fall within those A1 bounds — so ANSI D sheets now go through as well.
Why this matters
Large-format assembly drawings, weldments, and layout sheets are very often authored at A1. Previously, teams working with these had to tile a master into multiple A2 (or smaller) sheets before sending them to us — extra steps, extra bookkeeping, and a higher chance of losing cross-references between zones.
With A1 support, a large share of those drawings can now be submitted as-is:
- Fewer manual steps — no pre-tiling for the most common large format.
- Cleaner references — title blocks, revision tables, and leader networks stay on a single sheet.
- Same guarantees — every other rule (resolution, file format, per-page evaluation) is unchanged.
What stayed the same
The paper-size cap is only one of two independent constraints, and the others are untouched:
- Resolution still matters. You must still meet the ≥ 200 DPI minimum, and we recommend 300–400 DPI. A larger sheet means more pixels: A1 at 200 DPI is roughly 4677 × 6622 px. Don't downscale a drawing to "fit" — it only shrinks text and symbols and hurts OCR.
- A0 is still rejected. Very large sheets (A0) tend to carry hundreds of callouts and dense annotation networks that degrade precision and latency. If your master is A0, split it into logical A1 (or smaller) sheets by view zone or assembly section, keeping consistent title blocks and references.
- Per-sheet evaluation is unchanged. Each page of a multi-page PDF is checked independently. A single A0 page in an otherwise-valid file will be rejected for that page only.
Best practices
To get the most out of the expanded limit:
- Keep every sheet A1 or smaller (≤ 594 × 841 mm).
- Prefer vector PDF export from CAD; avoid "fit to page."
- Pair large raster content with ≥ 300 DPI.
- Maintain full borders and title blocks — they help us infer the intended paper size.
- For A0 masters, tile into multiple A1/A2 sheets with clear cross-references.
For the full specification — acceptance rules, DPI targets, vector vs. raster handling, and FAQ — see the Werk24 documentation.
As always, if you hit a DRAWING_PAGE_SIZE_TOO_LARGE error after following the guide, send us a sample (redacted if needed) along with your export settings and we'll help you pick the best strategy.