# Resize images for every platform

> Add your images, choose the packs you need, and fix any crop before downloading. Everything happens in your browser.

Source: https://getoxtro.com/image-resizer

This is an interactive tool. Use it at https://getoxtro.com/image-resizer; it runs in the browser.

## How to use the image resizer

1. Drop your images anywhere on the page, or choose **Try a sample image** to see how it works.
2. Click the subject of the image. Every crop moves to keep it in frame.
3. Switch on the packs you need, and set the file size each pack's files should stay under.
4. Click any crop to correct just that one: drag to move it, or zoom in.
5. Click **Make files**, then **Download ZIP**.

If you change a crop afterwards, only the files that changed are made again.

## The packs

**Social** makes every platform size as JPEG. **Website** makes four widths as WebP and AVIF, and adds a `<picture>` code snippet for each image to the ZIP. **Ads and email** makes five display ad sizes and an email header.

You can also make your own pack with any sizes, and send it to a colleague or client as a link. They open the link and have the same pack, with no account needed. The pack travels in the part of the link after the `#`, which browsers do not send to any server.

## Sizes in the packs

| Output | Size in pixels | Notes |
| --- | --- | --- |
| Instagram Story | 1440 × 2560 | Keep the subject out of the top 14% and bottom 35%, which can be covered |
| Instagram portrait | 1440 × 1800 | 4:5 |
| Square post | 1200 × 1200 | 1:1 |
| Pinterest pin | 1000 × 1500 | 2:3 |
| LinkedIn post | 1200 × 628 | 1.91:1 |
| X post | 1600 × 900 | 16:9 |
| YouTube thumbnail | 1920 × 1080 | 16:9, and held under 2 MB so it can also be uploaded from a phone |
| Facebook cover | 851 × 315 | Held under 100 KB, as Facebook suggests for the best loading speed |
| Display ads | 300 × 250, 336 × 280, 300 × 600, 728 × 90, 320 × 100 | Held under the 150 KB limit for Google image ads |
| Email header | 1200 × 400 | Twice the usual 600-pixel email column, for sharp screens |
| Website | 1600, 1200, 800 and 400 wide | Keeps the shape of your image, and skips any width larger than your image |

Platforms change these. The sizes here were last checked in November 2026.

## How the file size target works

The resizer looks for the best quality that stays under your target. It never changes the pixel size to get there, because a platform size has to stay exact.

Some images are too detailed to reach a small target. When even the lowest quality is too big, the file is still made, marked as over target on screen, and listed in the report in the ZIP, so you can raise the target or simplify the image.

## What is in the ZIP

Images are sorted into a folder per pack, then a folder per image, and named with their output and size, such as `Social/launch/launch-square-1200x1200.jpg`.

`report.txt` lists any files that failed, missed their target, became larger than the original, were enlarged from a smaller source, or have a subject the platform may cover. The Website pack adds `snippets.html`, with the code for each image.

Metadata such as camera details and location is left out of every file, because the images are drawn fresh from their pixels.

## Limits

- Up to 50 images at a time, each up to 60 MB.
- JPEG, PNG, WebP, AVIF and the first frame of a GIF. HEIC photos from iPhones work only in browsers that can read them, such as Safari. In others, the image is marked as unreadable.
- Colours are converted for normal screens, so wide-colour photos may look slightly less saturated.
- AVIF is much slower to make than the other formats, so a large Website batch can take a few minutes. Switch AVIF off in the pack if you do not need it.

## Frequently asked questions

### Are my images uploaded anywhere?

No. Your images are processed on your own device, by code running in your browser, and never reach our server. If you accept analytics in the cookie banner, we count runs and downloads, but never file names or images.

### Is it really free?

Yes. There is no account, no watermark, and you can use the files commercially.

### Why does my image look soft in one size?

The source image is smaller than that output, so it had to be enlarged. The crop is marked with how much. A larger source fixes it.

### Why did a website width not appear?

The Website pack skips widths larger than your image, because enlarging would add file size without adding detail.

### Can I keep the folders from a dropped folder?

Not yet. You can drop a folder and every image inside it is added, but the ZIP is organised by pack and image name. Images with the same name get separate folders, so nothing is overwritten.