Inches to pixels converter, how many pixels a size needs.

To convert inches to pixels, multiply the inches by the PPI (pixels per inch). So 8 inches is 768 pixels at 96 PPI, 1,200 pixels at 150 PPI and 2,400 pixels at 300 PPI. The more pixels per inch you ask for, the more pixels the file must have to fill the same size.

How to use the converter

1. Type the amount in the Inches (in) box. A decimal such as 2.5 or a fraction such as 3/4 works.
2. Pick the Pixels per inch (PPI) in the side column: 72, 96 (the CSS inch), 150, 300, 600 or Custom to type your own.
3. The big result shows Pixels (px). The cards under it give centimeters, millimeters, points and CSS pixels.
4. Look at The same amount at every PPI to compare all five presets at once. Click a PPI in that table to use it.
5. Drop a picture on Your picture to read its size in pixels and its print size at each PPI. Use the width and Use the height send that number to the converter.
6. Copy result and Copy link keep the answer. Start again resets the page. The swap button turns pixels into inches and back.

How many pixels does a print need

Work out each side on its own: width in inches × PPI, then height in inches × PPI. The table shows a few common print sizes at three PPI values. The pixel figure is the smallest file that fills the print at that density, so a bigger file is fine and a smaller file will be stretched.

Inches to pixels on a web page

On the web, the W3C CSS Values and Units Module Level 4 says 1 inch is 96 CSS pixels, so a box set to 6.5 inches is 624 pixels wide, and an 8.5 inch wide page is 816 pixels. That is a rule of CSS. It is not the size of anything on a real screen, which depends on its own pixel density. For a screen's true density use the PPI calculator.

Fractions and points

The box takes fractions, so 3/8 inch or 5 1/2 inches works. A point is 1/72 of an inch, so any length in points becomes pixels with a PPI of 72. A 36 point margin is half an inch, which is 48 pixels at 96 PPI and 150 pixels at 300 PPI. The card named Points (1/72 in) shows the point value for whatever you type.

Worked examples

• A 4 × 6 inch photo at 300 PPI. 4 × 300 = 1,200 and 6 × 300 = 1,800, so the file needs 1,200 × 1,800 pixels.
• A 3.5 × 2 inch card at 300 PPI. 3.5 × 300 = 1,050 and 2 × 300 = 600, so 1,050 × 600 pixels.
• A 24 × 36 inch poster at 150 PPI. 24 × 150 = 3,600 and 36 × 150 = 5,400, so 3,600 × 5,400 pixels, which is 19.44 megapixels.
• A 1 inch box on a web page. 96 CSS pixels.
• Half an inch at 72 PPI. 0.5 × 72 = 36 pixels, the same as 36 points.
• Back the other way. 2,400 pixels at 300 PPI is 8 inches. Press the swap button and type 2400.

Where the numbers come from

A pixel has no fixed size in inches, so the factor is the PPI you pick. The one official definition is on the web: the W3C CSS Values and Units Module Level 4 (Working Draft of 12 March 2024, checked 27 Oct 2026) says that 1 inch = 2.54 cm = 96 CSS pixels and that 1 point is 1/72 of an inch. NIST also lists the inch as exactly 2.54 cm (SP 811, Appendix B.8, checked 27 Oct 2026). For print there is no official PPI rule that I could find, so the page does not claim one. The converter keeps every figure as an exact fraction and rounds only the last digit shown.

Mistakes to avoid

The first is using 72 for a print that needs far more detail. At 72 PPI an 8 × 10 inch print needs only 576 × 720 pixels, against 2,400 × 3,000 at 300. The second is stretching a small file to fill a big print: the PPI then drops, and the print looks soft. The third is rounding too early. Keep the exact figure, then round the final pixel count to a whole number, which the line under the result does for you.

Related pages: Pixels to inches, PPI calculator, Inches to cm and Aspect ratio calculator.