📐 Resize Image in CM
Resize image in CM online — enter exact centimetre dimensions with DPI selector for web, screen or print. All processing in your browser. No signup required.
Drop your image here or click to upload
JPG, PNG, WebP supported · Set width and height in CM with DPI selector
About This Resize Image in CM Tool
A resize image in CM tool converts any digital image to exact centimetre dimensions for print, form submissions and professional documents. Enter a width and height in centimetres, select the appropriate DPI for your output medium, and the tool converts your CM measurements to pixels using the formula pixels = cm × DPI ÷ 2.54 before resizing the canvas accordingly. All processing runs in your browser — no files are uploaded to any server.
Resizing an image in centimetres is necessary whenever a physical print dimension is specified rather than a pixel dimension — passport photos, government ID uploads, print designs, school worksheets and medical forms all commonly specify image requirements in centimetres. This resize image in CM tool handles the pixel conversion automatically, removing the need for manual calculation.
The tool uses the HTML5 Canvas API to resize the image to the exact pixel dimensions corresponding to your CM size and DPI selection. Four DPI presets are available: 72 DPI (web), 96 DPI (screen, default), 150 DPI (medium print) and 300 DPI (high quality print). The pixel preview updates in real time as you change dimensions or DPI, confirming the output pixel size before you click Resize Image.
Output format matches the input: JPEG and WebP inputs produce JPEG at 85% quality; PNG inputs produce PNG at full quality. This ensures photographic images stay in the efficient JPEG format and graphics with transparency preserve their PNG quality in the output.
How to Resize an Image in CM
How It Works
- Upload your JPG, PNG or WebP image using the upload area above
- Enter your desired width and height in centimetres in the input fields
- Select the DPI setting that matches your intended output — 96 DPI for screen, 300 DPI for print
- Check the pixel preview to confirm the output pixel dimensions before resizing
- Click Resize Image — the Canvas API converts your CM dimensions to pixels and resizes the image
- Download your resized image and use it for print, forms or professional documents
The CM-to-pixel conversion formula is: pixels = cm × DPI ÷ 2.54. For example, a 10cm × 8cm image at 96 DPI becomes 378 × 302 pixels; the same dimensions at 300 DPI become 1181 × 945 pixels. The pixel preview in the settings panel shows this calculation in real time so you can compare the output at different DPI settings before committing to a resize.
For government form uploads and ID photo requirements that specify centimetre dimensions, select 300 DPI to ensure the print output matches the requirement precisely. For digital display uses such as presentations or web banners specified in CM, use 96 DPI. Use the Image Cropper to adjust the aspect ratio first if your image does not match the target CM proportions, then resize here for the exact dimensions.
Who Needs to Resize Images in CM
Centimetre-based image resizing is needed in contexts where physical dimensions — not pixel dimensions — are the specification. These are the most common use cases:
- Print designers and photographers — print layouts specified in centimetres require images resized to the exact CM dimensions at the correct print DPI; this tool converts the CM specification to the exact pixel canvas in one step
- Government form uploads requiring CM dimensions — many national ID applications, visa forms and official document portals specify photo dimensions in centimetres with a DPI requirement; resize image in CM here before uploading
- ID and passport photo preparation — passport photos worldwide are specified in CM (e.g. 3.5cm × 4.5cm for UK passports, 5cm × 5cm for US passports); this tool resizes to the required CM size at 300 DPI for print-ready output
- Teachers and students creating worksheets — educational materials prepared in CM to match A4 or letter page layouts need images sized in centimetres to fit precisely into the page margin grid without resampling in the word processor
Explore all our Image Tools for resizing, compressing, converting and cropping images.
Frequently Asked Questions
How do I resize an image in cm?
Upload your image using the tool above, enter your desired width and height in centimetres, select the DPI setting that matches your intended output (96 DPI for screen, 300 DPI for print), then click Resize Image. The tool converts your CM dimensions to pixels using pixels = cm × DPI ÷ 2.54 and resizes the canvas accordingly. All processing happens in your browser — no file is uploaded to any server.
How do I convert image size from pixels to centimetres?
To convert image pixels to centimetres, divide the pixel dimension by the DPI and multiply by 2.54. For example, a 300px wide image at 96 DPI is 300 ÷ 96 × 2.54 = 7.94 cm wide. This tool shows you the output pixel dimensions for any CM size and DPI combination in real time in the pixel preview, so you can verify the conversion before resizing.
What DPI should I use for print images?
Use 300 DPI for high-quality print output — the standard for photos, brochures and professional printed materials. Use 150 DPI for medium-quality print such as posters, internal documents and draft proofs. Use 96 DPI for screen display and web graphics. Use 72 DPI for web images where file size is the priority. At 300 DPI, a 10cm × 10cm image is 1181 × 1181 pixels — sufficient for crisp print reproduction at that physical size.
How do I resize a passport photo to specific cm dimensions?
For a standard passport photo (3.5cm × 4.5cm), upload your portrait photo, enter 3.5 in the width field and 4.5 in the height field, select 300 DPI for print quality, then click Resize Image. The output will be 413 × 531 pixels at 300 DPI — the correct pixel size for most passport photo print services. Download and print at 300 DPI to produce a 3.5 × 4.5 cm physical passport photo.
What is the relationship between cm, pixels and DPI?
Pixels, centimetres and DPI are related by: pixels = cm × DPI ÷ 2.54. DPI defines how many pixels correspond to one physical inch; since 1 inch equals 2.54 cm, dividing by 2.54 converts the DPI rate to pixels-per-centimetre. A 5cm dimension at 96 DPI is 5 × 96 ÷ 2.54 ≈ 189 pixels; the same 5cm at 300 DPI is 5 × 300 ÷ 2.54 ≈ 591 pixels. The pixel preview in this tool updates in real time as you change CM dimensions or DPI.
Can I resize an image to exact centimetres for printing?
Yes — enter the exact width and height in centimetres, select 300 DPI (or 150 DPI for medium-quality print), click Resize Image and download. The output file will contain pixel dimensions that correspond exactly to your specified CM size at the chosen DPI. When you print this file at the same DPI setting in your print dialog, the image will reproduce at precisely the dimensions you specified.
What image format is best for print after resizing in cm?
JPEG at 85% quality is best for photographic print images after resizing in cm — it produces sharp results at manageable file sizes. PNG is better for images with transparency, flat colours, logos or text overlays where lossless quality is required. This tool preserves your input format: JPEG and WebP inputs produce JPEG output; PNG inputs produce PNG output. For professional print workflows, PNG ensures no additional compression artefacts are introduced.