Image Resizer in millimeters

Enter your desired print size in mm, choose DPI, and we’ll resize your photo instantly. Perfect for precise printing, framing, or design.

mm to pixels Precision print 300 DPI ready

Drag & Drop an image here

or click to select (JPG, PNG, GIF, WEBP)

Resize by millimeters

Original

Name: -

Dimensions: -

Size: -

Resized (print preview)

Pixel dimensions: -

File size: -

Physical size: - (at 300 DPI)

Width (mm)

Height (mm)

DPI (print quality)

Processing is 100% local. Images never leave your device. Pixel dimensions are calculated from mm and DPI using 1 inch = 25.4 mm.

100% Secure

All processing stays in your browser. No uploads.

Millimeter precision

Set dimensions in mm for exact print sizes.

Aspect ratio lock

Keep proportions perfect while resizing.

Print ready

See physical size in mm & inches based on DPI.

What is this tool?

This is a pure millimeter-based image resizer. You enter the desired width and height in millimeters, select a DPI (dots per inch) value, and we calculate the exact pixel dimensions needed for a crisp print. Perfect for photographers, designers, and anyone needing precise physical dimensions.

How to use (mm only)

Upload your image

Drag & drop or click to select a JPG, PNG, etc.

Enter mm dimensions

Type the width and height you want in millimeters. Use the lock to keep the original aspect ratio.

Choose DPI

Select the print resolution (300 DPI for high quality, 150 for posters, 72 for web).

Resize & download

Click “Resize” to generate the new image, then download it. The file format matches your original.

Who should use this?

Graphic designers preparing print layouts, photographers ordering prints, engineers needing exact dimensions, and anyone who requires millimeter precision.

Frequently Asked Questions

How are pixels calculated from mm?

We use the formula: pixels = (mm ÷ 25.4) × DPI. For example, 100 mm at 300 DPI becomes (100/25.4)*300 ≈ 1181 pixels.

What DPI should I use for a standard photo print?

300 DPI is the industry standard for high‑quality photo prints. For large format (like posters), 150–200 DPI is often sufficient.

Will the image look pixelated if I enlarge it?

Enlarging any image beyond its original pixel dimensions may cause softness. We recommend starting with a high‑resolution original if you need a large print.

Is my image uploaded to your server?

No! All resizing is done locally in your browser using JavaScript. Your image never leaves your device.