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Print & Layout

Paper Size Conversion (mm to inches)

Convert A-series paper sizes from millimeters to inches and compare them with US Letter, Legal, and Tabloid. Understand rounding and margin differences before you print or design.

A0–A10Letter & LegalRounding guidanceB/C seriesUS ANSI

Conversion formulas

inches = mm ÷ 25.4

mm = inches × 25.4

Displayed values are rounded to two decimals for readability; calculations remain exact for layout and print planning.

Need custom sizes?

Use the mm to inches converter to handle custom dimensions with full decimal precision, then apply rounding as needed for printing.

DPI to pixels calculator

Convert paper dimensions to pixel sizes using common DPI presets. Supports A-series and US Letter/Legal/Tabloid with portrait/landscape orientation.

A4 Paper Size

Select a paper size and DPI to get pixel dimensions. Toggle orientation to match your layout.

Dimensions (in)
8.27 × 11.69 in
Pixels
2480 × 3508 px
Quick presets
Printers may add margins; include 3 mm bleed and a 3–5 mm safe area for critical content.

Display controls

Switch unit and orientation. Copy dimensions quickly for your design specs.

Unit
Orientation

A-series sizes

A0–A10 in millimeters and inches.

SizeDimensions (mm)Copy
A0841 × 1189
A1594 × 841
A2420 × 594
A3297 × 420
A4210 × 297
A5148 × 210
A6105 × 148
A774 × 105
A852 × 74
A937 × 52
A1026 × 37

US paper sizes

Letter, Legal, Tabloid in inches and millimeters.

SizeDimensions (mm)Copy
Letter215.9 × 279.4
Legal215.9 × 355.6
Tabloid279.4 × 431.8

US ANSI sizes

ANSI A–E engineering formats.

SizeDimensions (mm)Copy
ANSI A215.9 × 279.4
ANSI B279.4 × 431.8
ANSI C431.8 × 558.8
ANSI D558.8 × 863.6
ANSI E863.6 × 1117.6

Set orientation to match your drawing layout. For portrait, width × height. For landscape, height × width.

B-series sizes

B0–B10 in millimeters and inches.

SizeDimensions (mm)Copy
B01000 × 1414
B1707 × 1000
B2500 × 707
B3353 × 500
B4250 × 353
B5176 × 250
B6125 × 176
B788 × 125
B862 × 88
B944 × 62
B1031 × 44

C-series sizes (envelopes)

Designed to fit A-series paper.

SizeDimensions (mm)Copy
C0917 × 1297
C1648 × 917
C2458 × 648
C3324 × 458
C4229 × 324
C5162 × 229
C6114 × 162
C781 × 114
C857 × 81
C940 × 57
C1028 × 40

Aspect ratio notes

  • ISO 216 A-series uses a fixed √2 ratio (~1:1.414). Halving or doubling preserves shape.
  • US sizes vary: Letter ~1.294, Legal ~1.647, Tabloid ~1.545. Not a single standard ratio.
  • B- and C-series follow ISO logic; C envelopes are sized to hold A sheets with room to spare.
  • For pixel dimensions, use DPI presets or see the full chart on mm-to-inches chart.

Poster & Photo sizes

Common photo and poster formats.

Photo sizes

SizeDimensions (mm)Copy
Photo 4×6101.6 × 152.4
Photo 5×7127 × 177.8
Photo 8×10203.2 × 254
Photo 11×14279.4 × 355.6

Poster sizes

SizeDimensions (mm)Copy
Poster 12×18304.8 × 457.2
Poster 18×24457.2 × 609.6
Poster 24×36609.6 × 914.4
Poster 27×40685.8 × 1016

Envelope pairing (C-series ↔ A-series)

C3 fits A3

C4 fits A4

C5 fits A5

C6 fits A6

C7 fits A7

C8 fits A8

C9 fits A9

C10 fits A10

Comparison tips

A4 vs Letter

A4 is slightly narrower (210 mm vs 216 mm) and taller (297 mm vs 279 mm). Expect small margin differences when printing across regions.

A3 vs Tabloid

A3 is narrower and shorter than Tabloid. Scaling to fit may leave extra margin or slight crop depending on printer settings.

Rounding

Values are shown to two decimals for readability. Calculations are exact using 1 in = 25.4 mm; printers may still add margin offsets.

Frequently Asked Questions

Convert sizes before you print

Use the mm to inches converter for custom dimensions, then apply the A-series and US references to keep layouts consistent across regions.

Paper Size Conversion — mm to inches (A, B, C & US/ANSI)