# Resize PNG

> A free online tool that makes a PNG smaller in pixels by percent, longest side, or width and height, and keeps transparency; it never makes a picture larger.

Resize PNG files in a few clicks with this free online tool, and keep your transparent backgrounds when you need them. Use it as a simple png resizer when you want smaller pixel dimensions for a website, a chat app or a document. The tool keeps the proportions of your picture, so you do not have to work out the height yourself.

## Key facts

- Input: a PNG, JPG, WebP, AVIF, GIF, BMP or TIFF up to 5 MB in the free tool and 10 MB when signed in, and up to 16 MP (4096 x 4096); the type is read from the file content.
- Settings: size by percent (1 to 100), longest side or width and height (1 to 16384 px, proportions kept, fits inside the box); save as PNG, WebP, JPEG or GIF; a picture already smaller than the size asked for keeps its size.
- In our test a generated 2400 x 1600 px PNG of 80 KB became 1200 x 800 px and 63 KB at 50 percent, and a transparent PNG kept its transparency; the test pictures were generated by our scripts and results vary.
- Free without an account: up to 10 conversions per minute and 50 per day per visitor, no watermark. Signed in, each render costs 1 credit (100 free credits every month).
- Files are deleted automatically: 10 minutes after conversion without an account, 1 day with a free account.
- Developers can run the same job with POST https://api.aiipworld.com/v1/image-jobs?op=image_resize (the image as the request body, settings in the query string) and an API key (see the API docs page).

## How it works

1. Upload one PNG file. The tool shows a preview and the image size before you start.
2. Under "How to set the size", choose percent of the original, longest side in pixels, or width and/or height. The default is 50 percent.
3. Leave "Save as" on PNG, or pick WebP, JPEG or GIF if you need a different format.
4. Check "Keep transparency" if your picture has transparent areas. It is on by default.
5. Click "Resize PNG" and download the result. Download links are short-lived, so save the file soon after it is ready.

## How to resize PNG files

Resizing a PNG takes one upload and one setting. Start with the percent option if you want the same picture at a smaller scale. Start with width or height if the picture must fit a certain space on a page or in an app.

The tool handles one picture at a time. Each job is checked for type, size and pixel count before upload, so you see a problem early. When the job ends, the result panel shows the new pixel size and file size.

## Resize by percent, longest side or width and height

You can set the new size in three ways. Percent of the original accepts values from 1 to 100. Longest side sets the length of the longer edge in pixels, from 1 to 16384.

Width and/or height also go from 1 to 16384 pixels. An empty box means automatic, so the other side follows the proportions of the picture. In our tests, a 2400 x 1600 px PNG at width 800 gave 800 x 533 px, and the height followed on its own.

- Percent: 50 percent of a 2400 x 1600 px PNG gave 1200 x 800 px.
- Longest side: 1000 gave 1000 x 667 px.
- Box of 600 x 600: gave 600 x 400 px, fitted inside with nothing cropped.

## The tool never makes a PNG bigger

This tool only reduces pixel size. It will not enlarge a picture, even if you type a larger width. In our test, a 2400 x 1600 px PNG with width 4000 stayed 2400 x 1600 px, and the result panel said it was not resized.

If you need a larger picture, this tool cannot do it. Use a different editor for enlargement.

## Transparent PNG files stay transparent

"Keep transparency" is on by default, so a transparent PNG stays transparent after resizing. In our test, a transparent 1600 x 1200 px PNG sticker with a soft shadow became an 800 x 600 px PNG at 50 percent. The transparent corner stayed fully transparent.

If you save as JPEG, JPEG has no transparency. The transparent areas are filled with white. Choose PNG or WebP output when you need to keep the transparent background.

## Save as PNG, WebP or JPEG

The "Save as" list offers PNG, WebP, JPEG and GIF. This page opens with PNG selected. PNG keeps transparency and is the usual choice for a resized PNG.

The file size changes with the format. In our test, a 2400 x 1600 px PNG of 80 KB at 50 percent was 63 KB as PNG, 33 KB as JPEG and 13 KB as WebP. Your results will vary with the picture.

- PNG: keeps transparency when Keep transparency is on.
- WebP: quality slider from 1 to 100, default 80.
- JPEG: quality slider from 1 to 100, default 80, no transparency.

## PNG file size after resizing

Smaller pixel dimensions usually mean a smaller file. A 3000 x 2000 px PNG illustration of 165 KB became 1500 x 1000 px and 76 KB at width 1500. Measurements were made on pictures we drew ourselves, not on real photographs.

Resizing is not compression: the tool does not reduce colours to make the file smaller. If you need a smaller file at the same pixel size, use the Compress PNG tool.

## Photos stored rotated

Some pictures store their orientation in a tag rather than in the pixels. The tool turns these pictures upright before resizing. In our test, an 800 x 400 JPG with orientation 6 became upright, and at 50 percent it gave 200 x 400 px.

This turning applies to still pictures. It is not applied to animations.

## Limits: file size and pixels

Each image can be up to 5 MB in the free web tool. Signed-in users can upload up to 10 MB per image. Each picture can be up to 16 MP (4096 x 4096).

The tool accepts PNG, JPG, WebP, AVIF, GIF, BMP and TIFF. It does not accept SVG, PDF, HEIC or camera RAW files. Files are checked by their content, not by their name. A file that is not an image is refused with an "unsupported image" message.

- Results larger than 20 MB fail with an "output too large" message.
- A picture over the pixel limit is refused before it is decoded.

## Resize PNG from code

You can resize a PNG with the API. Send a POST request to https://api.aiipworld.com/v1/image-jobs?op=image_resize. The body is the raw image bytes, not JSON or multipart. Set Content-Type to image/png for a PNG.

Add your settings to the query string. Use format=png to keep a PNG result. Use exactly one of scale, max_side, or width and/or height. Authenticate with Authorization: Bearer `<API key>` or with x-api-key.

The API returns 202 with a job_id. Poll GET /v1/jobs/:id until the job succeeds, fails or times out. This page shows a ready cURL, Node and Python example based on the settings you choose. The API takes one request per image, and there is no batch endpoint.

Possible errors are 400 invalid_params, 400 or 422 unsupported_image, 413 file_too_large, 402 insufficient_credits and 429 rate limited.

## Privacy: what happens to your file

Your picture is sent to our server, where it is resized. The uploaded image is used only to make the result. It is deleted as soon as the job ends, whether it succeeds or fails.

The result is deleted after 10 minutes in the free web tool, and no history is kept. Camera and location tags are not copied into the result. You must have the right to use the picture you upload, as set out in our Acceptable Use Policy.

## Questions

### Can I resize a PNG for free?

Yes, you can resize a PNG for free in the web tool. Free use is limited to 5 MB per image and 30 images per day per visitor.

### How do I resize a PNG to a specific width?

Choose width in "How to set the size" and type the width in pixels. Leave the height box empty so the height follows the proportions of the picture.

### Can I make a PNG bigger?

No, this tool only makes a picture smaller. If you enter a larger size, the result keeps its original size and the panel says it was not resized.

### Does resizing keep the transparent background?

Yes, Keep transparency is on by default, so a transparent PNG stays transparent when the output is PNG. If you save as JPEG, the transparent areas are filled with white.

### Will resizing PNG files lower the quality?

Resizing recalculates the pixels, so fine details can soften. How much changes depends on the picture, so results vary.

### How do I make a PNG file smaller without changing its size?

Use the Compress PNG tool. This tool changes the pixel size, while Compress PNG is the better fit for keeping the same pixel size with a smaller file.

### Can I resize several PNG files at once?

No, the tool handles one picture at a time. The API also takes one request per image and has no batch endpoint.

### Can I resize to an exact width and height?

The box mode keeps the proportions and fits the picture inside the box, so the result may be smaller on one side. For exact sizes with cropping, use the YouTube Thumbnail Resizer or Resize image to 1080x1920 tools.

### What happens to a very large PNG?

A picture over 16 MP (4096 x 4096) is refused from its header before it is decoded. A result larger than 20 MB fails with an "output too large" message instead of returning a cut-off file.

### Can I resize a PNG in my own code?

Yes, the API accepts a raw PNG body with the image_resize operation. Use format=png to keep a PNG result, and see the Resize PNG from code section for the endpoint and error codes.

### Can I resize a PNG to 500x500?

Yes, choose "Make smaller: width and height" under "How to set the size" and type 500 in both boxes. The picture keeps its proportions and fits inside the box, so a 1600 x 1000 px picture gives 500 x 313 px in our test: this page does not crop to a square. A 1000 x 1000 px square gives 500 x 500 px, and a picture already smaller than 500 px keeps its size.

## Related

- [YouTube Thumbnail Resizer](https://aiipworld.com/tools/youtube-thumbnail-resizer/index.md)
- [Resize Image to 1080 x 1920](https://aiipworld.com/tools/resize-image-to-1080x1920/index.md)
- [PNG to GIF Converter](https://aiipworld.com/tools/png-to-gif/index.md)
- [Discord Banner Size and Image Resizer](https://aiipworld.com/tools/discord-image-resizer/index.md)
- [Twitch Emote Resizer](https://aiipworld.com/tools/twitch-emote-resizer/index.md)

Page: https://aiipworld.com/tools/resize-png/