How many images at once?

There is no fixed limit. They are processed one at a time with a running count. Very large images in large numbers will use a lot of memory on a modest device, so the page may feel slower.

Are my images stored?

No. Everything happens in the browser and nothing is sent to a server. Closing the page discards whatever was loaded.

Will a transparent PNG turn black as a JPEG?

No. JPEG cannot hold transparency, so transparent areas are filled with white before encoding. If you need a different background or want to keep the alpha channel, choose PNG or WebP instead.

Turn off "Never enlarge" and it will scale up to whatever you ask for, but detail that was not captured cannot be recovered; the result is simply softer. The option is on by default.

Does it handle HEIC from an iPhone?

It works wherever the browser can decode HEIC, which Safari can. Other browsers often cannot, and in that case the row says so and the remaining files still run.

How is resizing different from compressing?

Resizing changes the pixel count. Compressing keeps the pixel count and encodes it more coarsely. For a requirement stated in pixels ("no wider than 1200px"), use this; for one stated in bytes ("under 1MB"), the compressor is the better fit.

WebP is smaller than JPEG at a comparable look and it keeps transparency. JPEG opens absolutely anywhere. Pick WebP for the web, JPEG when you do not control what will open the file or when a printer asked for it.

How many pixels do I actually need?

It depends on where the image will be seen. For a web page or an email attachment, a long edge of 1200–1920px is usually plenty. Print is specified by density rather than dimensions, and around 300dpi at final size is the usual expectation (an A4 page at that density is roughly 3500px on its long edge).

What does 50% actually remove?

Each edge is halved, so a quarter of the pixels remain. The file shrinks roughly in step with the pixel count, though the exact figure depends on the format and the picture.

Back to all tools／ Images

Image resize

Runs in your browserNothing is uploaded

Set a long edge, a width, a height or a percentage and resize a batch of images at once. The aspect ratio is always kept, the reduction happens in steps so edges stay clean, and phone photos come out the right way up.

Input

Output size

Drag across the picture to change the size. It snaps to common dimensions.

Never enlarge

Stretching a small image adds no detail — it only softens the edges. On by default.

Set an exact number (long edge, width, height, %)

Dimensions

Size by

Long edge (px)

Whichever edge is longer becomes this value, portrait or landscape. Common choices: 1920 (full HD), 1600, 1200, 800.

Common values

4000 × 3000 px → 1600 × 1200 px (×0.40)

Diagram and export settings (format, quality)

Dimension drawing

Sample 4000×3000

Original
Output
Ratio 4:3

Export

Output format

"Keep original" preserves JPEG, PNG and WebP. Formats a browser cannot write (HEIC and friends) become PNG if they might carry transparency, JPEG otherwise.

Output

The resized images land here, with the before/after size and dimensions.

Shrinking to less than half in one step roughens edges, so the image is stepped down and then finished. Phone photos are read with their orientation tag and never come out rotated.

All tools

Highlights

Downscales in steps to protect detail: A single canvas draw down to a quarter size or less loses thin lines and text and leaves diagonal edges jagged. This reduces by no more than half per pass, so detail survives better.
Photos stay upright: Phone cameras store landscape pixels plus an EXIF rotation flag. The flag is applied before processing, so the output is not turned on its side.
Nothing is uploaded: Reading, resizing and encoding all happen in the page, so photos of people and internal documents are fine to use.

How to use it

Add your images
Click the box to choose files, or drag them in. Several at once is fine, and each one shows its original dimensions in the list.
Set the size
Choose long edge, width, height or percent, then type a number — or take one of the common values. The line underneath shows the original dimensions and what they become.
Resize and save
Press Resize and the files are processed one at a time. Save them individually from the download button on each row, or use "Download all as ZIP" when there is more than one.

Choosing the settings

How is resizing different from compressing?: Resizing changes the pixel count. Compressing keeps the pixel count and encodes it more coarsely. For a requirement stated in pixels ("no wider than 1200px"), use this; for one stated in bytes ("under 1MB"), the compressor is the better fit.
JPEG or WebP?: WebP is smaller than JPEG at a comparable look and it keeps transparency. JPEG opens absolutely anywhere. Pick WebP for the web, JPEG when you do not control what will open the file or when a printer asked for it.
How many pixels do I actually need?: It depends on where the image will be seen. For a web page or an email attachment, a long edge of 1200–1920px is usually plenty. Print is specified by density rather than dimensions, and around 300dpi at final size is the usual expectation (an A4 page at that density is roughly 3500px on its long edge).
What does 50% actually remove?: Each edge is halved, so a quarter of the pixels remain. The file shrinks roughly in step with the pixel count, though the exact figure depends on the format and the picture.

Questions

How many images at once?: There is no fixed limit. They are processed one at a time with a running count. Very large images in large numbers will use a lot of memory on a modest device, so the page may feel slower.
Are my images stored?: No. Everything happens in the browser and nothing is sent to a server. Closing the page discards whatever was loaded.
Will a transparent PNG turn black as a JPEG?: No. JPEG cannot hold transparency, so transparent areas are filled with white before encoding. If you need a different background or want to keep the alpha channel, choose PNG or WebP instead.
Can it enlarge?: Turn off "Never enlarge" and it will scale up to whatever you ask for, but detail that was not captured cannot be recovered; the result is simply softer. The option is on by default.
Does it handle HEIC from an iPhone?: It works wherever the browser can decode HEIC, which Safari can. Other browsers often cannot, and in that case the row says so and the remaining files still run.