Paper size · US envelopes

6 × 9 envelope size

6 × 9 Envelopes: 152.4 × 228.6 mm, with inch and cm dimensions. Check proportions and common uses. Find the largest square for a paper craft.

152.4 × 228.6 mm6 × 9 inRatio 2:3 (1:1.5)
Millimetres
152.4 × 228.6 mm
Centimetres
15.24 × 22.86 cm
Inches · rounded to 4 decimals
6 × 9 in
Aspect ratio · width:height
2:3 (1:1.5)
This sizeA4
6x9 catalog envelope and A4, at the same scale. Sheets shown with the short edge across.

Common uses

Choose an envelope with space around the contents, especially for several sheets or a thick card. The dimensions describe the closed envelope, excluding its flap.

What it holds

It takes a 5.5 × 8.5 inch Half Letter sheet, or a Letter sheet folded once.

How it compares

9x12 catalog envelope is larger in area. These formats have their own proportions; halving a sheet does not necessarily produce the next size.

From sheet to fold

Cut a square for origami

The largest square from a flat rectangle this size is 152.4 × 152.4 mm (6 × 6 in). Fold one short edge against a long edge so their corners meet. Crease the diagonal, cut off the extra 76.2 mm strip, then open the triangle.

These are the closed envelope dimensions. For an actual envelope, open the seams first and measure the usable flat paper before cutting. Try the beginner origami dog with your square, or see how to prepare square paper.

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