How to Convert Inches to Pixels: Formula, CSS, and Print Examples

Last updated: August 12, 2026.

If you need a quick inches-to-pixels conversion, start with the resolution you actually need. There is no single answer to “how many pixels are in an inch”: a web layout uses CSS pixels, while an image prepared for print uses a chosen pixel density such as 300 pixels per inch (PPI).

Quick answer: pixels = inches × PPI. At 96 PPI, 1 inch is 96 pixels; at 300 PPI, 1 inch is 300 pixels. For CSS, 1in is defined as 96px, but one CSS pixel is not guaranteed to be one physical pixel on a high-density display.

Choose the right conversion before calculating

“Inches to pixels” describes two related jobs:

• Web and CSS: use the CSS length rule, 1in = 96px. This is a layout conversion, not a measurement of the physical pixels in a particular screen.
• Images and print: choose the image resolution in PPI, then multiply the physical size by that PPI. A printer’s DPI describes ink dots, so it is not interchangeable with an image’s PPI.

That distinction is the useful part of the calculation. If a print shop gives you a required PPI, use that value. If you are setting a CSS width, use CSS pixels. If neither requirement is specified, report the PPI alongside the result instead of presenting one number as universal.

1. Use the inches-to-pixels formula

The basic formula for an image or print document is:

pixel dimension = physical dimension in inches × PPI

For example, a 2-inch image at 300 PPI is:

2 × 300 = 600 pixels

So a square image intended to print at 2 × 2 inches at 300 PPI should be 600 × 600 pixels before any cropping or resampling. The same 2-inch square at 150 PPI is 300 × 300 pixels.

Common inch-to-pixel examples

For a rectangular document, calculate width and height separately. An 8 × 10-inch page at 300 PPI is 2,400 × 3,000 pixels. Do not multiply the two physical dimensions together unless you are calculating total area; the output dimensions are still width × height.

2. Use an online inches-to-pixels converter

An online inches-to-pixels converter or calculator is useful when you need several values quickly. The important control is the PPI field. Enter the physical size, confirm whether the tool calls the setting PPI or DPI, and check the formula before using the result in a design or print order.

A calculator that returns “1 inch = 96 pixels” is answering the CSS convention. A calculator set to 300 PPI is answering a print-image question. Neither setting is automatically correct for every device, image, or printer.

3. Set the size in design software

Design applications usually let you specify inches, pixels, and resolution together. In Photoshop, the Image Size controls separate pixel dimensions from printed size and resolution. If you change physical size without resampling, the pixel count can remain unchanged; if you enable resampling, the software adds or removes image data to create new pixel dimensions.

For a print file, enter the required width and height in inches, set the requested PPI, and inspect the resulting pixel dimensions. For a screen asset, set the pixel dimensions directly unless a production specification explicitly gives you a physical size and density.

4. Automate an inch-to-pixel conversion

For repeated conversions, a small function is less error-prone than copying values between tools:

def inches_to_pixels(inches, ppi):
    return round(inches * ppi)

print(inches_to_pixels(3, 300))  # 900

Keep the PPI as an input rather than hard-coding 96 or 300. Rounding is appropriate when the output must be a whole pixel, but keep the unrounded value if you are comparing several layouts or preserving a precise physical specification.

5. Check the device or production specification

If the target is a particular display, printer, scanner, or print service, use its documented specification. A device’s total screen resolution—such as 1920 × 1080—does not tell you its physical pixel density without the screen dimensions. Likewise, a printer’s DPI is an ink-placement specification, not necessarily the PPI your image should use.

For a screen, distinguish between the application’s CSS or logical pixels and the device’s physical pixels. Responsive layouts normally use CSS units and let the browser map them to the display. For a print job, follow the printer or service provider’s supplied PPI, trim, bleed, and color requirements.

CSS inches are not physical screen measurements

CSS defines 1in as 96px. That rule makes a web layout predictable, but it does not promise that a 96-pixel element will measure exactly one physical inch on every monitor or phone. High-density screens can map one CSS pixel to multiple device pixels, and browsers account for viewing and device conditions.

Use CSS pixels when the question is “how wide should this element be in a web page?” Use PPI when the question is “how many image pixels should this physical print size contain?” Mixing those two answers is the most common source of a misleading inch-to-pixel conversion.

Which method should you use?

• One quick answer: apply pixels = inches × PPI and state the PPI.
• Web layout: use the CSS convention of 96 CSS pixels per inch, while remembering that CSS pixels are logical units.
• Print or image export: use the PPI required by the print workflow; 300 PPI is a common high-quality starting point, not a universal rule.
• Many conversions: use a calculator, spreadsheet, or short script that keeps PPI explicit.
• Specific hardware: check the manufacturer or print-service specification instead of guessing from a common screen resolution.

Sources and update notes

The CSS relationship used here is documented in MDN’s CSS length reference. The distinction between image PPI, pixel dimensions, and printer DPI follows Adobe’s Photoshop resolution guidance and its explanation of print-resolution choices. This 2026 refresh removes unsupported device-trend claims, stale tool lists, undated screenshots, and the old 2025 headline while keeping the original five-method structure and the search intent for inch-to-pixel conversion. For publication context, see About 10Beasts.

Reviewed August 12, 2026. Technical rules and print recommendations can vary by browser, application, device, and production workflow; verify the receiving service’s specification before ordering a print job.