Dimensions Of RA & SRA Series Untrimmed Paper Sizes
The RA and SRA paper formats are defined by ISO 217 "Paper - Untrimmed Sizes" and cover untrimmed raw paper for commercial printing. The RA and SRA sizes are slightly larger than the corresponding A series sizes to allow for bleed on printed material that will be later trimmed to size, often for bound publication.
RA stands for "raw format A" and is conceptually defined as being 105% of the A series size, thus as A0 has an area of 1 square metre RA0 has an area of 1.05 square metres. SRA stands for "supplementary raw format A" and is conceptually defined as being 115% of the A series size, so a sheet of SRA0 paper has an area of 1.15 square metres. In reality the sizes for RA0, RA1, RA2, SRA0, SRA1 and SRA2 are rounded to the nearest centimetre and sizes for RA3, RA4, SRA3 and SRA4 are rounded to the nearest half centimetre.
Table of RA Untrimmed Paper Sizes RA0 to RA4
Size | Width x Height (mm) | Width x Height (in) |
---|---|---|
RA0 | 860 x 1220 mm | 33.9 x 48.0 in |
RA1 | 610 x 860 mm | 24.0 x 33.9 in |
RA2 | 430 x 610 mm | 16.9 x 24.0 in |
RA3 | 305 x 430 mm | 12.0 x 16.9 in |
RA4 | 215 x 305 mm | 8.5 x 12.0 in |
To obtain paper sizes in centimetres, convert mm values to cm by dividing by 10.
The aspect ratio (the ratio of the width to the height) of the RA sheets is 1:root 2 (1:1.4142) as for the A series sheets.
Table of SRA Untrimmed Paper Sizes SRA0 to SRA4
Size | Width x Height (mm) | Width x Height (in) |
---|---|---|
SRA0 | 900 x 1280 mm | 35.4 x 50.4 in |
SRA1 | 640 x 900 mm | 25.2 x 35.4 in |
SRA2 | 450 x 640 mm | 17.7 x 25.2 in |
SRA3 | 320 x 450 mm | 12.6 x 17.7 in |
SRA4 | 225 x 320 mm | 8.9 x 12.6 in |
To obtain paper sizes in centimetres, convert mm values to cm by dividing by 10.
The aspect ratio (the ratio of the width to the height) of the SRA sheets is 1:root 2 (1:1.4142) as for the RA series sheets.
Note: Unlike the US untrimmed paper sizes, the RA and SRA paper sizes do not form any part of the calculation of paper weight.
See the following link for Uncut English Paper Sizes from before the introduction of ISO 216.
SRA1+, SRA2+, SRA3+ and SRA3++
Some sizes that are becoming more popular due to their extra width being good for newer printing machines are SRA1+, SRA2+ SRA3+ and SRA3++. These SRA plus sizes give a little extra width for a printer to grab the edge of the paper to turn it over for double sided printing, as the printer will slightly mark the paper when it picks it up. It should be noted that these sizes are not defined by an ISO standard and have emerged from industry needs.
Size | Width x Height (mm) | Width x Height (in) |
---|---|---|
SRA1+ | 660 x 920 mm | 26.0 x 36.2 in |
SRA2+ | 480 x 650 mm | 18.9 x 25.6 in |
SRA3+ | 320 x 460 mm | 12.6 x 18.1 in |
SRA3++ | 320 x 464 mm | 12.6 x 18.3 in |