How to Resize an Image in CM?
- Upload your image. Drag it into the box above or click Choose Image. JPG, PNG and WebP files up to 10 MB are supported.
- Enter the size. Type the width and height in centimetres, or tap a preset such as 3.5 × 4.5 cm.
- Set the DPI. Pick 72, 96, 150, 200 or 300 DPI, or type a custom value. The output size in pixels updates as you type.
- Choose how to fit. Fit adds a background, Fill crops the edges, Stretch changes the shape. Pick the one your photo needs.
- Click Resize Image and download. The file is saved to your device with the exact centimetre dimensions you asked for.
Everything runs locally: your photo never leaves your device, and nothing is uploaded to a server.
What Does Image Size in CM Mean?
When an image is sized in centimetres, the number refers to its physical size when printed. A photo resized to 10 × 15 cm prints exactly 10 cm wide on paper. On a screen the same file can look any size, because screens show pixels rather than physical units.
CM sizing matters whenever the final image has to match a physical object: a printed photograph, a photo frame, an ID or application form, a certificate, or a card. If the destination is a website or a phone screen, pixels are usually the unit you want instead.
CM vs Pixels vs DPI
The three terms describe different things, and the tool needs all of them to produce a correct file.
| Term | What it measures |
|---|---|
| CM | The physical size of the image when printed — for example 3.5 × 4.5 cm. |
| Pixels | The digital width and height of the image file — for example 413 × 531 px. |
| DPI | Pixel density: how many pixels are packed into each printed inch. It links digital pixels to a physical size. |
Change the DPI and the same CM size produces a different pixel count. That is why DPI matters for print: it decides how sharp the printed image looks.
How to Convert CM to Pixels?
The relationship is simple:
Pixels = (CM ÷ 2.54) × DPI
One inch equals 2.54 cm. So a 3.5 cm width at 300 DPI is (3.5 ÷ 2.54) × 300 ≈ 413 pixels, and a 4.5 cm height at 300 DPI is about 531 pixels. The result is roughly 413 × 531 pixels.
This tool performs the conversion automatically. The Output line above shows the pixel result live as you change the CM values or the DPI.
Resize a Photo to 3.5 × 4.5 CM
The 3.5 × 4.5 cm size is commonly requested for ID-style photos on application forms in India and many other countries. Tap the preset in the tool (or type the numbers) and the output at 300 DPI is about 413 × 531 pixels.
Two honest notes: official photo requirements vary by authority, so always read the form’s specification before submitting. And because most phone photos are wider than a 3.5 × 4.5 cm box, use Fill to crop the edges cleanly or Fit to keep the whole image with a background. Avoid Stretch here — a distorted face photo will be rejected.
Resize Images for Printing
Printers lay out images at physical size, so centimetre dimensions matter for anything printed: passport and visa photos, application forms, certificates, framed prints and photo cards. The DPI you choose controls how many pixels represent each printed centimetre.
For photo-quality printing, 300 DPI is a common choice; for simple documents 150 DPI is often enough. If a print shop gives you a pixel size instead of a centimetre size, use the pixel image resizer for that request. Before printing, make sure your print dialog is set to 100% or “Actual Size” so the printer does not scale your file.
Resize Image in CM Without Distortion
The most common mistake is stretching. When your target CM size has a different shape (aspect ratio) than the photo, there are three honest choices:
- Fit — the whole image fits inside the box and the leftover space becomes a background colour.
- Fill — the image covers the whole box and the edges are cropped away.
- Stretch — the image is forced to the exact box and its shape changes.
This tool offers all three modes, so the result is never distorted without your knowledge. If you want to keep the photo’s original shape while changing one dimension, turn on Lock aspect ratio.
CM Image Resizer vs Pixel Resizer
Both tools change image size, but they answer different questions. This page works in centimetres — physical, print-oriented dimensions for forms, photos and documents.
The resize image by pixels tool works in width × height pixels — digital dimensions for websites, social templates and design specs. Enlargement is a separate task again: it makes a small image bigger, which no CM or pixel entry does by itself.
And if a form limits the file size rather than the dimensions — for example a 20KB or 100KB maximum — dimension tools will not help. Use the dedicated size tools to resize an image to 20KB or reduce an image to 100KB instead. Pick the tool that matches the actual requirement, not the one closest by name.
Frequently Asked Questions
How do I resize an image in cm?
Upload a JPG, PNG or WebP image, enter the width and height in centimetres (or tap a preset such as 3.5 × 4.5 cm), choose a DPI, pick how the image should fit, and click Resize Image. The resized file downloads to your device. Everything is processed locally in your browser.
How do I resize a photo to 3.5 × 4.5 cm?
Select the 3.5 × 4.5 cm preset, or type 3.5 in the width box and 4.5 in the height box. At 300 DPI the output is about 413 × 531 pixels. Official photo requirements vary by authority, so always check the form’s specification.
How do I convert cm to pixels for an image?
Multiply the centimetre value by the DPI and divide by 2.54: Pixels = (CM ÷ 2.54) × DPI. For example, 3.5 cm at 300 DPI is about 413 pixels. The tool shows this conversion automatically as you type.
What DPI should I use when resizing an image in cm?
It depends on where the image will be used. 72–96 DPI is fine for screens, 150 DPI suits simple documents, and 300 DPI is a common choice for photo-quality printing. There is no universal rule: if a form specifies a DPI, use that value.
Can I resize a JPG image in cm?
Yes. JPG and JPEG images are fully supported and the resized result downloads as a JPG.
Can I resize a PNG image in cm?
Yes. PNG images are supported and stay as PNG when downloaded. Transparency is preserved in Fit mode when you choose a transparent background.
What is the difference between cm and pixels?
Centimetres describe the physical printed size of an image. Pixels describe the digital width and height of the image file. DPI connects the two: it states how many pixels are packed into each printed inch.
Can I resize an image in cm without losing quality?
Making the image smaller in pixels usually keeps quality. Making it larger creates new pixels by estimation, so it can soften. Start with the largest, cleanest original you have, keep the DPI reasonable, and avoid enlarging more than necessary.