Size of paper A3
- A3 paper size in millimetres is 297 mm x 420 mm.
- A3 paper size in inches is 11.7 in x 16.5 in.
Envelopes for A3 paper
- For an unfolded A3 you will need an C3 envelope.
- Fold the A3 paper once – C4 envelope.
More A papers formats
See all paper sizes in A series.