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Size & Dimensions

Paper Size Guide:
A4 vs A5 (Booklet) vs A3

By OnlinePrintout Team3 min read

"Will my notes look too small on A5?" "Is A3 big enough for a poster?"
Paper sizes can be confusing because the numbers go backwards: A3 is bigger than A4! Here is a simple visual guide.

The Golden Rule

A4 is the standard.
A3 = Two A4 pages side-by-side (Double Size).
A5 = Half an A4 page (Booklet Size).

1. A4 Size (Standard)

Dimensions: 210 x 297 mm
This is what you use in your home printer. It is the global standard for almost everything.

  • Best For: Thesis, Official Documents, Agreements, Assignments.
  • Our Price: Standard rates apply.

2. A5 Size (Booklet Mode)

Dimensions: 148 x 210 mm
A5 is exactly half of A4. When you select "2 Pages Per Sheet" on our website, you are effectively printing in A5 size.

  • Why Students Love It: It saves 50% paper and money. It creates a cute, handy "booklet" that is easy to carry.
  • Best For: UPSC Notes, Revision Cards, Pocket Guides.
  • How to Order: Select 2 Pages Per Sheet in options.

3. A3 Size (Poster)

Dimensions: 297 x 420 mm
A3 is large. It is used when you need to see a lot of detail at once.

  • Best For: Engineering Drawings, Medical Charts, Art Portfolios, Flowcharts.
SizeDimensions (mm)Common Use
A3297 x 420Posters, Charts
A4210 x 297Standard Documents
A5148 x 210Booklets, Pocket Notes

Ready to print?