What’s the Size of A4 Paper? – Complete Guide to Paper Sizes

Home » What’s the Size of A4 Paper? – Complete Guide to Paper Sizes

What’s A4 size paper? Is A3 bigger than A4 paper? Is A4 the same as 8.5 x 11? You can find all your questions answered about international paper sizes in this post. 

One of the most common paper sizes used globally (including the UK but excluding North America and parts of Latin America) is A series, also known as international paper sizes.

The A-series is defined by ISO 216 (the international standard for paper sizes).

A series of paper sizes go from A0 to A10.

The most common paper from the A-series is called A4.

What’s a4 size paper?

A4 paper size print dimensions:

210 x 297 mm

(8.27 x 11.69 in)

Image showing dimensions for portrait A4 and landscape A4 paper.

A4 is a paper size 210 millimeters wide and 297 millimeters long. 

It is a commonly used size internationally (apart from the US and Canada – and parts of Latin America), and in most cases, A4 is the default paper size for a wide range of documents like letters and forms, and it’s the standard paper size for most home printers and office printers.

What’s the difference between A3, A4, and A5?

A4 is half of the size of A3 and double the size of A5. 

So when you fold A3 in half, it becomes A4. And when you fold A4 in half, it becomes A5 and so on.

The same width and height ratio always applies.

For example. the short edge of A5 is half the long edge of A4 paper. Or, if you double the short edge of A4, you’ll get the long edge of A3.

Paper Sizes: A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10 according ISO 216 (image)

Image of paper sizes from A0 to A10 without dimensions (A4 paper size included)
Paper sizes from A0 to A10 without dimensions (A4 paper size included)
Paper sizes guide table A0 to A10 (A4 included)
Paper sizes guide table A0 to A10 (A4 included)
Image of paper sizes from A0 to A10 with dimensions (A4 paper size included)
Paper sizes from A0 to A10 with dimensions (A4 paper size included)

The length of the smaller size is always the width of the larger size.

The dimensions of A sized paper series (table)

So what are the dimensions of A-sized paper? The range begins with the smallest A10 and goes all the way to A0.

A-series paper size dimensions in millimeters (including A4 paper size)

Paper sizeWidth (mm)Length (mm)Dimensions (mm)
A0841 mm1189 mm841 × 1189
A1594 mm841 mm594 × 841
A2420 mm594 mm420 × 594
A3297 mm420 mm297 × 420
A4210 mm297 mm210 × 297
A5148 mm210 mm148 × 210
A6105 mm148 mm105 × 148
A774 mm105 mm74 × 105
A852 mm74 mm52 × 74
A937 mm52 mm37 × 52
A1026 mm37 mm26 × 37
Table: A-series paper size dimensions in millimeters (including A4 paper size)

A-series paper size dimensions in inches (including A4 paper size)

Paper sizeWidth (in)Length (in)Dimensions (in)
A033.1 in46.8 in33.1 × 46.8
A123.4 in33.1 in23.4 × 33.1
A216.5 in23.4 in16.5 × 23.4
A311.7 in16.5 in11.7 × 16.5
A48.3 in11.7 in8.3 × 11.7
A55.8 in8.3 in5.8 × 8.3
A64.1 in5.8 in4.1 × 5.8
A72.9 in4.1 in2.9 × 4.1
A82 in2.9 in2.0 × 2.9
A91.5 in2 in1.5 × 2.0
A101 in1.5 in1.0 × 1.5
Table: A-series paper size dimensions in inches (including A4 paper size)

What size is A10 paper?

Dimensions: 26 mm x 37 mm (2.6 x 3.7 cm / 1.0 x 1.5 inches)

  • Width: 26 mm (1.02 in)
  • Length: 37 mm (1.46 in)

What’s the A9 paper size?

Dimensions: 37 mm x 52 mm (3.7 x 5.2 cm / 1.5 x 2.0 inches)

  • Width: 37 mm (1.46 in)
  • Length: 52 mm (2.05 in)

What size is A8 paper?

Dimensions: 52 mm x 74 mm (5.2 x 7.4 cm / 2.0 x 2.9 inches)

  • Width: 52 mm (2.05 in)
  • Length: 74 mm (2.91 in)

What’s the A7 paper size?

Dimensions: 74 mm x 105 mm (7.4 x 10.5 cm / 2.9 x 4.1 inches)

  • Width: 74 mm (2.91 in)
  • Length: 105 mm (4.13 in)

What size is A6 paper?

Dimensions: 105 mm x 148 mm (10.5 x 14.8 cm / 4.1 x 5.8 inches)

  • Width: 105 mm (4.13 in)
  • Length: 148 mm (5.83 in)

What’s the A5 paper size?

Dimensions: 148 mm x 210 mm (14.8 x 21.0 cm / 5.8 x 8.3 inches)

  • Width: 148 mm (5.83 in)
  • Length: 210 mm (8.27 in)

What size is A4 paper?

Dimensions: 210 mm x 297 mm (21.0 x 29.7 cm / 8.3 x 11.7 inches)

  • Width: 210 mm (8.27 in)
  • Length: 297 mm (11.69 in)

What’s the A3 paper size?

Dimensions: 297 mm x 420 mm (29.7 x 42.0 cm / 11.7 x 16.5 inches)

  • Width: 297 mm (11.69 in)
  • Length: 420 mm (16.54 in)

What size is A2 paper?

Dimensions: 420 mm x 594 mm (42.0 x 59.4 cm / 16.5 x 23.4 inches)

  • Width: 420 mm (16.54 in)
  • Length: 594 mm (23.39 in)

What’s the A1 paper size?

Dimensions: 594 mm x 841 mm (59.4 x 84.1 cm / 23.4 x 33.1 inches)

  • Width: 594 mm (23.39 in)
  • Length: 841 mm (33.11 in)

What size is A0 paper?

Dimensions: 841 mm x 1,189 mm (84.1 x 118.9 cm / 33.1 x 46.8 inches)

  • Width: 841 mm (33.11 in)
  • Length: 1,189 mm (46.81 in)

A0 length is, in other words, over a meter long.

What are paper sizes bigger than A0?

The paper sizes that are bigger than A0 are called 2A0 and 4A0.

2A0 It is double the size of A0. The dimensions are 1189 x 1682 mm.

And 4A0 is double the size of 2A0, and the dimensions are 1682 x 2378 mm.

Paper sizeDimensions
2A0 1189 x 1682 mm
4A01682 x 2378 mm
Table: Dimensions in millimeters of paper sizes bigger than A0 (2A0 and 4A)

The difference between A4 and US letter paper sheets

US letter is wider than A4, but A4 is slightly larger in height.

Width (mm)Length (mm)Width (in)Length (in)
A4210 mm297 mm8.3 in11.7 in
Letter216 mm279 mm8.5 in11.0 in 
Table – A4 and US letter paper size dimensions in millimeters and inches

The width of A4 paper is 210 mm (8.3 inches), while the width of the US letter size paper is 216 mm (8.5 inches).

And the length of A4 is 297 mm (11.7 inches), while the length of the US Letter size paper is 279 mm (11 inches).

The difference between A4 and US letter size paper
The difference between A4 and US letter size paper

Is A4 the same as 8.5 x 11?

A4 is not the same as 8.5×11 which is the US letter.

Is A3 bigger than A4?

A3 is bigger than A4. And A4 is bigger than A5 and so on.

A3 is double the size of A4, and A4 is double the size of A5.

So the same way, A5 is half the size of A4 and A4 is half the size of A3.

Image showing two A4 size papers equal one A3 size paper.
Two A4 size papers equal one A3 size paper.

Tip: Remember always to include a paper margin (also known as a print bleed) when printing my calendars or other printables.