Resize an image to exact pixels
Pixels are what screens, websites and upload portals actually check. Choose Pixels and type the width you need. With the aspect ratio locked, the height is calculated for you, so the picture keeps its natural shape. Unlock it when both sides must be exact (for example, a form that asks for a photo of exactly 200 × 230 px).
Percentage is the quickest way to make a large photo smaller without thinking about numbers. 50% halves the width and the height, which leaves only a quarter of the pixels, so the file gets a lot lighter too.
The quick presets cover popular sizes:
- 600 × 600: a square image for profile pictures and product photos.
- 1080 × 1080: square posts for social media.
- 1280 × 720: HD (16:9) for video thumbnails, slides and blog headers.
- 1920 × 1080: Full HD for wallpapers, presentations and wide website banners.
Resize an image in cm, mm or inches
Printed documents and many application forms describe sizes in centimetres or inches: a 3.5 × 4.5 cm photo, a 4 × 6 in print, an A4 page. Choose Print size, enter the measurements in cm, mm or inches, and pick a DPI (dots per inch). The tool works out the pixels with a simple formula: pixels = inches × DPI, where one inch is 2.54 cm.
Common print sizes and their pixels at 300 DPI
| Print size | Pixels at 300 DPI | Typical use |
|---|---|---|
| 3.5 × 4.5 cm | 413 × 531 px | Passport-style photos in many countries |
| 2 × 2 in (5.1 × 5.1 cm) | 600 × 600 px | Square US-style photos |
| 4 × 6 in (10.2 × 15.2 cm) | 1200 × 1800 px | Standard photo prints |
| 5 × 7 in (12.7 × 17.8 cm) | 1500 × 2100 px | Larger prints and frames |
| A4 (21 × 29.7 cm) | 2480 × 3508 px | Full-page documents and posters |
Which DPI should you use? 300 DPI is the usual choice for sharp photo prints. 150–200 DPI is fine for documents and for posters viewed from a distance. If an online form gives a size in cm and also sets a small KB limit, a lower DPI such as 100–150 produces fewer pixels and a smaller file, which is easier to keep under the limit.
The DPI you choose is also written into the saved JPG or PNG. That matters when you insert the image into Word or send it to a print shop: the software reads the DPI and prints the picture at the physical size you set, instead of guessing.
Choosing a fit mode when width and height are both fixed
When your image and the target size have different shapes (a tall phone photo going into a square slot, for example), something has to give. Pick the option that suits your picture:
- Keep aspect (fit inside): the whole image is scaled to fit within the box without distortion. One side may come out smaller than the number you typed.
- Crop to fill: the image fills the exact size and the overflowing edges are trimmed. Best for profile photos, thumbnails and fixed-size form uploads.
- Pad with a background colour: the whole image is kept and the empty space is filled with a colour you choose, such as white. Useful for logos and product photos that must not be cut.
- Stretch: the image is forced to the exact dimensions. Fine for small changes, but faces and circles look distorted if the shape changes a lot.
Resizing vs. compressing
Resizing changes the dimensions: how many pixels wide and tall the image is. Compressing changes how efficiently those pixels are stored, which mainly affects the file size in KB. The two are linked: fewer pixels almost always means a smaller file.
If you need both (say a photo of 300 × 400 px under 50 KB), set the dimensions here and type 50 in the optional maximum file size box. Or resize first and then use Compress Image for full control over quality. For common limits there are ready-made pages such as compress image to 20KB and compress image to 100KB.
Tips for sharp resized images
- Shrinking is safe, enlarging is limited. Making an image smaller keeps it sharp. Making it much larger than the original can't add detail that was never captured, so a small image blown up to poster size will look soft.
- Start from the original file. Resizing a copy that has already been resized or heavily compressed loses a little more quality each time.
- Pick the right format. JPG for photos, PNG for screenshots, text and graphics with transparency, WebP for websites where you want the smallest files.
- iPhone photos work directly. HEIC files open without converting first, and photos come out the right way up because the camera's rotation is applied.
- Passport photos and signatures need more than a size. Use the Passport Photo Maker for head position and print sheets, and the Signature Resizer to crop and clean a signature.
Batch resize privately in your browser
Add dozens of images at once and they are all resized with the same settings, then downloaded together as a ZIP. Because the work happens on your own device, there's no upload wait and no copy of your photos on anyone's server, which matters when the images are ID documents, family photos or client work.
There's no sign-up, no watermark and no daily limit. Need a different format as well as a different size? The Image Converter turns HEIC, WebP and PNG into JPG and back.