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Inches to Pixels: The Conversion Formula, Reference Tables, and Free Tool

You have a print size in inches. You need to know how many pixels your image requires. The conversion is straightforward once you understand the one variable that connects physical and digital dimensions: DPI.

The formula:

pixels = inches × DPI

A 4×6 inch photo at 300 DPI needs 1200×1800 pixels. At 72 DPI, that same 4×6 inch area only needs 288×432 pixels.

DPI (dots per inch) defines how many pixels fit into one physical inch. Higher DPI means more pixels per inch, which means sharper output. The right DPI depends on where the image will be used — screen, home printer, or professional press.

Need to go the other direction? See our guide on converting pixels to inches.


Master Conversion Table: Inches to Pixels

This table covers the most common print and display sizes at three standard DPI values. Every number follows the formula: width in inches × DPI = width in pixels.

Standard Photo and Print Sizes

Size (inches) 72 DPI (Screen) 150 DPI (Presentation) 300 DPI (Print)
1 × 1 72 × 72 150 × 150 300 × 300
2 × 2 144 × 144 300 × 300 600 × 600
2 × 3 144 × 216 300 × 450 600 × 900
3 × 5 216 × 360 450 × 750 900 × 1500
4 × 6 288 × 432 600 × 900 1200 × 1800
5 × 7 360 × 504 750 × 1050 1500 × 2100
8 × 10 576 × 720 1200 × 1500 2400 × 3000
8.5 × 11 612 × 792 1275 × 1650 2550 × 3300
11 × 14 792 × 1008 1650 × 2100 3300 × 4200
16 × 20 1152 × 1440 2400 × 3000 4800 × 6000
18 × 24 1296 × 1728 2700 × 3600 5400 × 7200
24 × 36 1728 × 2592 3600 × 5400 7200 × 10800

Quick Reference for Common Use Cases

Use Case Typical Size (in) Recommended DPI Pixels Needed
Passport photo (US) 2 × 2 300 600 × 600
Wallet print 2.5 × 3.5 300 750 × 1050
Standard photo print 4 × 6 300 1200 × 1800
Letter/A4 document 8.5 × 11 300 2550 × 3300
Poster (small) 11 × 17 300 3300 × 5100
Poster (large) 24 × 36 150 3600 × 5400
Banner/billboard 48 × 96 100 4800 × 9600

You can resize your image to exact pixel dimensions with Pixotter — processing happens in your browser, no upload required.


When You Need This Conversion

Print Production

Print shops specify dimensions in inches but your camera and design software work in pixels. A printer requesting an "8×10 at 300 DPI" needs a 2400×3000 pixel image. Send them anything smaller and the output will look soft or pixelated. Send them a 72 DPI version of the same inch dimensions (576×720 pixels) and the print will be unusable.

Before sending files to a printer, verify your image meets the pixel requirements. You can check and change your image's DPI without altering the pixel data itself.

Display Advertising

Ad networks define creative sizes in both pixels and inches. A standard half-page magazine ad (4.625 × 7.5 inches) at 300 DPI requires 1388 × 2250 pixels. Digital display ads use lower DPI but still reference physical dimensions in media kits. Knowing the conversion prevents rejected submissions and reprints.

Presentation Slides

PowerPoint and Google Slides default to 10 × 7.5 inches at 96 DPI (960 × 720 pixels). If you embed a 200 × 150 pixel image into a full-slide background, it will look blurry on any projector. For sharp slides projected at 1080p, target at least 150 DPI — that means 1500 × 1125 pixels for a full-slide image.

Custom Framing and Canvas Prints

Custom frame shops and canvas print services ask for dimensions in inches. Your digital photo needs enough pixels to fill that frame at print quality. An 18×24 inch canvas at 300 DPI requires 5400×7200 pixels — roughly 39 megapixels. Most smartphone cameras (12-50 MP) can handle standard print sizes, but large format prints may require higher-resolution source images.

Check out our guide on standard photo dimensions for a complete list of common print sizes and their pixel equivalents.


What DPI Should You Use?

DPI is not a fixed property of an image — it is a setting that tells the output device how to map pixels to physical space. The same 3000×2000 pixel image can be printed at 10×6.67 inches (300 DPI) or 41.67×27.78 inches (72 DPI). The pixel count stays identical. Only the physical output size changes.

Choose DPI based on where the image will be displayed:

Output Type Recommended DPI Why
Web/screen display 72–96 Monitors display 72-96 pixels per inch. Higher DPI wastes file size without visible improvement.
Email attachments 96 Balances clarity with file size for on-screen viewing.
Presentations 150 Projected images benefit from extra detail, especially on large screens.
Home/office printing 200–300 Inkjet printers produce good results at 200+ DPI. 300 DPI is the safe default.
Professional photo printing 300 Industry standard. Most labs reject files below 300 DPI at the requested print size.
Magazine/offset printing 300+ Commercial printing demands 300 DPI minimum. Some processes require 400+.
Large format (posters, banners) 100–150 Viewed from a distance, so lower DPI is acceptable. A 24×36 poster at 150 DPI looks sharp from 3+ feet.
Billboard 30–72 Viewed from 20+ feet. High DPI is unnecessary and creates unmanageable file sizes.

For a deeper explanation of how DPI and PPI relate, read DPI vs PPI: what's the difference.


How to Resize Images to Exact Inch × DPI Dimensions

Once you know the pixel dimensions you need, resizing is simple:

  1. Calculate your target pixels. Multiply your desired width in inches by your target DPI. Do the same for height. Example: 5 × 7 inches at 300 DPI = 1500 × 2100 pixels.

  2. Open the Pixotter resize tool. Drop your image into the tool. No account needed, no upload — everything runs locally in your browser.

  3. Enter your target dimensions. Set the width to 1500 and height to 2100 (or whatever your calculation produced). Lock the aspect ratio if you want to preserve proportions, or unlock it to match exact dimensions.

  4. Set the DPI. Use the DPI changer to embed the correct DPI metadata in the output file. This tells printers and design software the intended physical size.

  5. Download. Your image is now sized correctly for your target output — ready to send to the printer, upload to the ad platform, or embed in your presentation.

If your source image has fewer pixels than your target, you are upscaling. Upscaling cannot create detail that was not captured — a 600×900 pixel image resized to 1200×1800 will be softer than one originally captured at 1200×1800. When possible, start with the highest resolution source available.

Need to hit exactly 300 DPI for a print job? Our guide on how to make an image 300 DPI walks through the process step by step. For general printing preparation, see resize image for printing.


Frequently Asked Questions

How many pixels is 1 inch?

It depends on the DPI. At 72 DPI (standard screen resolution), 1 inch = 72 pixels. At 300 DPI (standard print resolution), 1 inch = 300 pixels. There is no single answer without knowing the DPI.

How do I convert 4×6 inches to pixels?

Multiply each dimension by your target DPI. For print (300 DPI): 4 × 300 = 1200 pixels wide, 6 × 300 = 1800 pixels tall. For screen (72 DPI): 4 × 72 = 288 pixels wide, 6 × 72 = 432 pixels tall.

What size is 8.5 × 11 inches in pixels at 300 DPI?

8.5 × 300 = 2550 pixels wide. 11 × 300 = 3300 pixels tall. So a letter-size document at print quality is 2550 × 3300 pixels.

Is 72 DPI good enough for printing?

No. 72 DPI is designed for screen display. Printed at 72 DPI, images look pixelated and blurry. Most print services require 300 DPI minimum. Use 72 DPI only for images that will stay on screen — websites, social media, email. Learn more about how to change image DPI for different outputs.

Can I make a small image bigger by increasing the DPI?

Changing the DPI metadata alone does not add pixels. If your image is 600 × 400 pixels and you change the DPI from 72 to 300, the pixel count stays at 600 × 400. The image just prints smaller (2 × 1.33 inches instead of 8.33 × 5.56 inches). To print larger at high DPI, you need more pixels — which means either recapturing at higher resolution or upscaling (with some quality loss).

What pixel dimensions do I need for a poster?

For a standard 24 × 36 inch poster at 300 DPI: 7200 × 10800 pixels (roughly 78 megapixels). Most cameras cannot produce this natively. For posters, 150 DPI is usually sufficient since they are viewed from several feet away — that requires 3600 × 5400 pixels, which most modern cameras and phones can handle.


Quick Conversion Formulas

Keep these bookmarked:

For the reverse conversion (you have pixels and need inches), use our pixels to inches guide with its own reference tables.

Need to resize right now? Drop your image into the Pixotter resize tool — calculate your target pixels from the tables above, enter the dimensions, and download. No signup, no upload, processed entirely in your browser.