How do I resize a photo to 300 DPI and under 50 KB?

Add the photo, set the width and height, choose 300 DPI, choose JPG, enter 50 in Max KB, and click Resize photo. The result shows the final pixels, print size and file size.

How many pixels is 3.5 x 4.5 cm?

It depends on the DPI: 413 x 531 pixels at 300 DPI, 276 x 354 at 200 DPI. Switch the size to cm and pick the DPI, and the tool shows the pixels.

Is the DPI actually saved in the file?

Yes. It is written into the JPG header (JFIF) or the PNG pHYs chunk, which is where viewers and upload checks read it.

Why is my file still over the KB limit?

At very large pixel sizes even the lowest JPG quality can be too big. The tool tells you when that happens. Use fewer pixels, or the same cm size at a lower DPI.

Does this work with iPhone HEIC photos?

In Safari, yes. Other browsers cannot open HEIC; set your iPhone camera to "Most Compatible" or share the photo as JPG.

Is my photo uploaded?

No. Resizing, DPI and KB adjustment all happen in your browser.

Photo Resizer in KB, Pixel and DPI

Set the exact size a form asks for, in pixels, cm, mm or inches, choose the DPI, and keep the file between a minimum and maximum KB. The DPI is written into the file. Your photo never leaves your browser.

Loading image tool...

Can this make my photo fit the form?

The form gives pixels or cm, a DPI and a KB range

Enter all three. JPG output is tuned to fit the KB range at the exact pixel size.

The form only gives a KB limit

This works, but the KB-only tool also shrinks pixels when needed to reach very small sizes.

Compress image to a size

Making a blurry photo sharper by raising DPI

DPI is only a print label. It cannot add detail that is not in the original.

A passport photo with background removal

This tool resizes only. Use the passport photo maker for backgrounds and face framing.

Passport size photo maker

Features

Size in pixels, centimetres, millimetres or inches
DPI from 72 to 600 (or any custom value), saved inside the JPG or PNG
Min and max KB window, checked against both 1 KB = 1,000 and 1,024 bytes
Crop, add a white border, or stretch when the shape changes
Opens JPG, PNG, WEBP and more; HEIC in Safari
Removes camera details and location from the photo

When forms ask for it

Exam and job applications

Photo and signature uploads with fixed pixels, a DPI and a KB range.

Printing to a size

Get a photo that prints at exactly 3.5 x 4.5 cm or 2 x 2 inches.

Portals that check DPI

Some upload checks read the DPI stored in the file. This tool writes it.

Pixels, DPI and KB explained

How pixels, cm and DPI relate

DPI (dots per inch) says how many pixels make up one printed inch. So pixels = inches x DPI. A 3.5 x 4.5 cm photo at 300 DPI is 413 x 531 pixels; at 200 DPI it is 276 x 354 pixels. When a form gives the size in cm and a DPI, this tool works out the pixels for you.

Changing DPI does not add detail

DPI is a label that tells printers how big to print the pixels. Raising it without adding pixels makes the print smaller, not sharper. To make a small photo print large and sharp you need a higher-resolution original.

Hitting a KB limit

For a maximum KB the tool lowers JPG quality step by step, keeping the exact pixel size the form asked for.
For a minimum KB the JPG is padded with blank data that viewers ignore, so the picture does not change.
PNG has no quality setting, so its size cannot be tuned. Choose JPG when a KB limit matters.
Only need a KB limit, no fixed pixels? Use Compress Image to Size.
Need a passport photo with a white background? Use the Passport Size Photo Maker.