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Custom Image Resizer

Resize any image to exact dimensions in pixels, centimetres, inches or percent with DPI, aspect lock, fit modes, a target file size and live preview. Free, no upload.

Your images never leave your browser
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How to use the Custom Image Resizer

  1. 1Upload one image (or several for bulk mode).
  2. 2Type the width and height, and choose the unit: px, cm, inches or %.
  3. 3Set the DPI when working in cm or inches; lock the aspect ratio for proportional scaling.
  4. 4Pick a fit mode and, optionally, a target file size in KB.
  5. 5Check the live preview and download.

Resize to an exact size in px, cm, inches or percent

Forms and print jobs rarely speak in pixels. A visa portal wants 600×600 px under 240 KB, a printer wants 8×10 inches at 300 DPI, a college form says 3.5 cm × 4.5 cm, and a web designer asks for 60% of the original. The Custom Image Resizer accepts all of those directly. Type the width and height in whatever unit the instruction uses, set the DPI if it is a physical size, and it works out the pixels.

How it works

  1. Upload one image for the live preview, or several for a bulk run.
  2. Enter width and height and choose the unit: px, cm, in or %.
  3. When using cm or inches, set the DPI (300 for print, 72 or 96 for screens). Pixels equal size in inches multiplied by DPI, so 2 in at 300 DPI is 600 px.
  4. Lock the aspect ratio for proportional scaling, or unlock it and pick a fit mode (fit, pad, fill or stretch) for a fixed frame.
  5. Optionally set a target file size in KB; the encoder searches for the highest JPG or WebP quality that stays under it.

The preview updates as you type so you can see how a crop or padding will land before downloading.

Common conversions at 300 DPI

Physical sizePixels at 300 DPITypical use
35 × 45 mm413 × 531Pakistan, UK, Schengen and Australia passport photos
2 × 2 in (51 × 51 mm)600 × 600US and India passport photos
50 × 70 mm591 × 827Canada passport photo
4 × 6 in1200 × 1800Standard photo print
10 × 15 cm1181 × 1772Metric photo print
A4 (210 × 297 mm)2480 × 3508Full-page print

The same mm figure at 72 DPI would be a tiny 99×128 px, which is why DPI matters whenever a physical unit is involved. The DPI value is also written into the JPG so print shops read the intended size.

Why it matters

Exact sizes are pass or fail. Government upload forms reject 599×600. Amazon and Daraz compare pixel dimensions to hard limits, and a print lab will pad or crop anything that is not the ordered ratio. Being able to resize image to exact size in the unit the instruction uses removes the arithmetic, and the target-KB option covers the other half of most requirements, such as the 100 KB cap on the Pakistan online portal or 240 KB for a US DS-160 upload.

Tips

  • Lock the aspect ratio when only one dimension is specified, then use fill or pad when both are.
  • For a photo that must be a specific ratio, crop it with the Image Cropper first so you control what is trimmed.
  • To hit only a file size and keep the dimensions, the Photo Size Reducer to Exact KB is quicker.
  • For marketplace presets, the Marketplace Preset Resizer already knows every platform's numbers, and the Bulk Image Resizer handles hundreds of files with one rule.
  • Resize image in cm for print at 300 DPI; 150 DPI is acceptable for large posters viewed from a distance.

Privacy

Everything, including the live preview, runs in your browser with the Canvas API. Your images never leave your browser, and nothing is uploaded or logged, which matters when the photo is an ID or a passport picture.

Frequently asked questions

How do I resize a photo to 3.5 cm × 4.5 cm?

Choose cm as the unit, enter 3.5 and 4.5, and set DPI to 300. The tool converts that to 413×531 px and embeds 300 DPI in the JPG so it prints at the right physical size. Use fill mode so the face is centre-cropped to the exact ratio.

What DPI should I use?

300 DPI for anything that will be printed, such as passport photos, labels and product inserts. 72 or 96 DPI only matters when a form quotes a size in inches for screen use. DPI does not change pixel-based sizes at all; it only converts cm and inches into pixels.

Can it resize to an exact file size as well?

Yes. Set a target in KB and the tool re-encodes the resized image at decreasing JPG or WebP quality until it fits. Dimensions stay as you specified; only compression changes. PNG cannot be targeted this way because it is lossless.

Does percentage mode work with the other units?

Percentage scales relative to the original pixels, so 50% of a 3000×2000 image is 1500×1000. It ignores DPI. Switch to px, cm or in when you need an absolute size rather than a relative one.

Is there a bulk mode?

Yes. Drop several images and the same width, height, unit, DPI, fit mode and KB target apply to each. The live preview shows the first file; the rest are processed in Web Workers and bundled into a ZIP for download.

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