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Publishing trade size

A Format Book Size

Compare A Format

An A Format book measures 110 × 178 mm (4.33 × 7.01 in). It is the UK mass-market paperback trim, the small rack size sold in supermarkets, airports and station kiosks, and the smallest common book size.

inisDimensions 110 × 178 mm

A Format measures 110 millimetres wide and 178 millimetres tall.

A Format Dimensions in Each Unit

A Format is 110 × 178 mm, which is 11.0 × 17.8 cm or 4.33 × 7.01 in.

UnitWidthHeightWidth × heightCopy
Millimetres (mm)110178110 × 178 mm
Centimetres (cm)11.017.811.0 × 17.8 cm
Metres (m)0.110.1780.11 × 0.178 m
Inches (in)4.337.014.33 × 7.01 in
Feet (ft)0.360.580.36 × 0.58 ft
Points (pt)312505312 × 505 pt
Picas (pc)264226 × 42 pc
Pixels at 72 DPI312505312 × 505 px
Pixels at 150 DPI6501051650 × 1051 px
Pixels at 300 DPI129921021299 × 2102 px
Pixels at 600 DPI259842052598 × 4205 px

Pixel counts follow from the resolution: pixels = millimetres ÷ 25.4 × DPI. More on the DPI and pixels page.

A Format Shape and Area

Aspect ratio1 : 1.618
Area0.0196 m² · 19,580 mm²
Diagonal209.2 mm · 8.24 in
Closest ISO sizeUK rack paperback
Governing standardBook trade convention (UK and US)

A Format to Scale

A Format110 × 178 mm110 mm178 mm
A Format at true proportion. Long edge 178 mm, short edge 110 mm.

Put A Format next to another size in the comparison tool.

Frequently Asked Questions

What size is an A Format paperback?

A Format is 110 by 178 mm, or about 4.33 by 7.01 inches.

Is A Format related to ISO A paper sizes?

No. A Format is a UK publishing trade name for a paperback trim. It has no connection to ISO 216 A sizes despite the letter.

What is A Format used for?

Mass-market genre fiction, travel-retail editions and cheap backlist reprints.

Book Sizes

Dimensions per Publishing trade size; unit values derived by formula. Reviewed . Editorial Process →