Open Access Articles- Top Results for ISO 217

ISO 217

The ISO 217:1995 standard defines the RA and SRA paper formats.

These paper series are untrimmed raw paper. RA stands for “raw format A” and SRA stands for “supplementary raw format A”. The RA and SRA formats are slightly larger than the corresponding A series formats. This allows bleed (ink to the edge) on printed material that will be later cut down to size. These paper sheets will after printing and binding be cut to match the A format.

  • The ISO A0 format has an area of 1.00 m²
  • The ISO RA0 format has an area of 1.05 m²
  • The ISO SRA0 format has an area of 1.15 m²
RA Series Formats SRA Series Formats
RA0 860 × 1220 SRA0 900 × 1280
RA1 610 × 860 SRA1 640 × 900
RA2 430 × 610 SRA2 450 × 640
RA3 305 × 430 SRA3 320 × 450
RA4 215 × 305 SRA4 225 × 320


Paper in the RA and SRA series format is intended to have a <math>1:\sqrt{2}</math> aspect ratio but the dimensions of the start format have been rounded to whole centimetres.

For example, the RA0 format would be <math>\sqrt{1.05}*2^{-0.25} m \times \sqrt{1.05}*2^{0.25} m \approx 861.7 mm \times 1218.6 mm</math>, which has been rounded to <math>860 mm \times 1220 mm</math>.

The resulting real ratios are:

  • <math>43:61 \approx 1:1.4186</math> for RA0, RA2, RA4;
  • <math>61:86 \approx 1:1.4098</math> for RA1, RA3;
  • <math>45:64 \approx 1:1.4222</math> for SRA0, SRA2, SRA4;
  • <math>32:45 = 1:1.40625</math> for SRA1, SRA3.

Other ISO paper standards

  • ISO 216:1975, defines two series of paper sizes: A and B
  • ISO 269:1985, defines a C series for envelopes

External links