# A3 Paper Size: 297 × 420 mm, Inches & Pixels \| Paper & Scale

Canonical HTML source: [A3 Paper Size: 297 × 420 mm, Inches & Pixels \| Paper & Scale](<https://paper-and-scale.com/paper-sizes/a3/>).

This experimental Markdown representation quotes the public HTML page below. The HTML address above is the canonical publication.

---

## Quoted source content

> 1. [Home](<https://paper-and-scale.com/>)
> 2. [Paper sizes](<https://paper-and-scale.com/paper-sizes/>)
> 3. A3 paper
>
> FORMAT NOTES
>
> # A3 paper size.
>
> Room for a bigger idea. A3 is often used for posters, diagrams and booklets that fold down to A4.
>
> ![A3 paper dimensions, 297 by 420 millimetres](<https://paper-and-scale.com/images/paper-sizes-a3-figure-1.40cd9a391b.svg>)
>
> Nominal A3 dimensions in portrait orientation. The outline shows proportions; it is not displayed at physical size.
>
> ## What size is A3?
>
> 297 × 420 mm
>
> That is **29.7 × 42 cm**, or approximately **11.69 × 16.54 inches**. These are portrait dimensions. Swap width and height for landscape.
>
> An A3 sheet folds into two A4 pages. Check that your printer supports A3: many everyday desktop printers accept A4 or Letter as their largest format.
>
> ## A3 size in pixels
>
> Paper has physical dimensions; its pixel dimensions depend on the resolution you choose. The values below are rounded to the nearest whole pixel.
>
> | Image resolution | Width × height |
> | --- | --- |
> | 72 PPI | 842 × 1191 px |
> | 150 PPI | 1754 × 2480 px |
> | 300 PPI | 3508 × 4961 px |
> | 600 PPI | 7016 × 9921 px |
>
> At 300 PPI, a full A3 image is approximately 3508 × 4961 pixels. A folded four-page A4 booklet needs two A4 page positions per side of each A3 sheet.
>
> Already have an image? [Check its physical print size](<https://paper-and-scale.com/tools/pixels-to-print/>) at your chosen PPI.
>
> ## Printing and scaling A3
>
> To fit A4 artwork on A3, use approximately 141.4%. To fit A3 artwork on A4, use approximately 70.7%. Leave room for your printer’s non-printable margins.
>
> For a document that must retain its dimensions, select **Actual size** or **100%** in your print dialogue, check the preview, then measure a test print. [Read the actual-size printing guide](<https://paper-and-scale.com/guides/print-at-actual-size/>).
>
> [Calculate a print scale](<https://paper-and-scale.com/tools/print-scale/>)
>
> ## How much does a sheet weigh?
>
> At 80 gsm, one nominal A3 sheet weighs approximately **9.98 g**. Paper GSM measures mass per square metre, so heavier stock changes the result without changing the page dimensions.
>
> [Calculate paper weight](<https://paper-and-scale.com/tools/paper-weight/>) for your stock and number of sheets.
>
> A3 AT A GLANCE
>
> **Millimetres**
> 297 × 420
>
> **Centimetres**
> 29.7 × 42
>
> **Inches, approx.**
> 11.69 × 16.54
>
> **At 300 PPI**
> 3508 × 4961 px
>
> [Compare all paper sizes](<https://paper-and-scale.com/paper-sizes/>)
>
> ## Sources & method
>
> - [ISO 216:2007](<https://www.iso.org/standard/36631.html>) · Nominal paper dimensions
> - [Adobe A-series format reference](<https://www.adobe.com/uk/creativecloud/design/discover/a0-format.html>) · Published millimetre dimensions
> - [Adobe printed image resolution](<https://helpx.adobe.com/photoshop/desktop/crop-resize-transform/resize-adjust-resolution/printed-image-resolution.html>) · How pixels relate to printed size
>
> Dimensions use the published nominal sizes. Conversions and calculator examples are derived from those values. Calculated results are estimates for planning, not printer calibration.
>
> ## Keep things in proportion.
>
> [All print tools](<https://paper-and-scale.com/tools/>)
>
> [Print scale calculator A4 to A3? A3 to A5? Get the percentage that fits your page.](<https://paper-and-scale.com/tools/print-scale/>)[Pixels to print size Find out how large an image can print at your chosen resolution.](<https://paper-and-scale.com/tools/pixels-to-print/>)[Print sheet layout planner Compare layouts with bleed, margins and gaps. Export a plan you can measure.](<https://paper-and-scale.com/tools/print-layout/>)[Paper weight calculator From one sheet to a full ream. Estimate the weight using GSM.](<https://paper-and-scale.com/tools/paper-weight/>)

---

End of quoted source content.