Image tools

Tools for working with photos without sending them to anyone's server. Everything runs in your browser, using your own device's memory and CPU. Nothing is uploaded, stored, or logged.

What image tools actually do for you

An image tool fixes one of three problems: the file is too big, the dimensions are wrong, or the format is incompatible with whatever you are trying to put it into. Anything more elaborate is usually editing rather than processing, and is a job for a proper editor. The tools here keep the picture intact and adjust the wrapper.

The reason that matters in 2026 is that phone cameras now produce 4-to-12MB files by default, and most of the places those files are going to land (a website, an email, a CV, a marketplace listing) cannot deal with that, or will silently re-encode the image in ways you would not like if you saw the result. Doing the resize or compression yourself, in advance, leaves you in control of the output. It also means the original on your phone stays untouched.

Where the inputs come from

Mostly: your camera roll, a screenshot, or a download. A few practical notes.

  • Source resolution. Start with the original file rather than a copy that has already been compressed by a messaging app. WhatsApp, iMessage, and most social platforms re-encode images on the way through, which softens detail and adds artefacts. If you have the original, use it. The Photo Resizer will down-scale far more cleanly from a 4000-pixel original than from a 1080-pixel re-share.
  • Target dimensions. Find out what the destination actually wants before you resize. LinkedIn, eBay, Etsy, Companies House, and the DVLA all publish exact pixel sizes for the spots they expect images in. Resizing to the right number first is much tidier than resizing twice.
  • Aspect ratio. If you need a specific shape (16:9 for a video thumbnail, 1:1 for a profile picture, 4:5 for an Instagram portrait) work that out before you start cropping. The Aspect Ratio Calculator handles the maths so you do not end up with a picture that is almost the right shape and slightly squashed.
  • Format. JPG for photographs, PNG for screenshots and graphics with sharp edges or transparency, WebP for the web when you control the receiving end, HEIC for Apple devices that can read it. Sending a HEIC to a Windows user who has never installed the codec is the modern equivalent of sending a fax to a houseplant.

Common mistakes people make with images

Up-scaling is the worst one. Making a 600-pixel image into a 2400-pixel image does not add any detail; it just stretches the existing pixels and adds blur. If a destination needs a bigger image than you have, retake it or find a higher-resolution source. No browser tool can invent detail that was never captured.

Compressing twice is the second. Each pass of JPG compression throws information away, so a file that has been saved as JPG, edited, and saved as JPG again is noticeably softer than one that was compressed only on the way out. Edit in PNG or the source format, compress once at the end. The Image Compressor is happy to take a PNG in and give a JPG out so you only pay the compression cost once.

The third is shipping huge images for no reason. A 3MB hero image on a website costs every visitor real time to download, especially on mobile, and Google's Core Web Vitals score notices. Most web images do not need to be more than 200 to 400KB, and almost none need to be more than 1MB. Check the file size before you upload, not after.

How to choose between the tools here

If the file is too big for an upload form, compressor first. If the picture is the wrong size, resizer. If the receiving end refuses the format, converter. If you are setting up a graphic from scratch and need the right shape, aspect ratio. We will keep adding format converters as new ones get common enough to matter (AVIF is on the list), and the order on the page roughly tracks how often each one gets reached for.

  • Photo Resizer

    Resize and convert photos in your browser. Pick a width, a height, a format and a quality. Your image never leaves your device.

  • WebP to JPG Converter

    Convert WebP images to JPG or PNG in your browser. Drag and drop, bulk conversion, optional resize. Fixes the Chrome WebP problem in Word, Outlook and PowerPoint.

  • Image Compressor

    Compress JPG, PNG and WebP photos to a target file size, like 2 MB for an upload form or 500 KB for email. Multiple files at once, no upload.

  • HEIC to JPG Converter

    Convert iPhone HEIC and HEIF photos to JPG, PNG or WebP in your browser. Drop one file or a holiday's worth, get downloads back. Files never leave your device.

  • Aspect Ratio Calculator

    Work out the matching width or height that keeps an image or video at the same aspect ratio. Live two-way binding, simplified ratio shown via GCD, preset ratios in one click.

  • Image File Size Estimator

    Estimate the file size of a JPEG, PNG, WebP, AVIF or HEIC from its pixel dimensions and quality, before you encode anything. Side-by-side comparison of all five formats.

  • Color Depth & Storage Calculator

    Calculate the uncompressed size of an image at any bit depth, the total colours that depth can represent, and how it compares to a typical JPEG or PNG.

  • Image DPI / Print Size Calculator

    Convert between pixels, DPI and print size in either direction. Quality verdict tells you whether the print will look sharp or visibly pixelated.

Frequently asked questions

What format should I save my photos in?

JPG for photographs going on the web, PNG for screenshots and images with transparency, WebP if you can be sure the audience uses modern browsers (everyone except very old systems). AVIF is now well supported and gives the smallest files for the same quality, but it is slower to encode. The Photo Resizer exports to whichever you pick.

Should I shrink images for the web before uploading?

Yes. A camera or phone shot is typically 4 to 8 MB at full resolution. The largest visible size on most websites is around 1,200 to 1,800 pixels wide. Resizing to the actual display size (and re-saving at 80 to 85 per cent quality) typically cuts the file by 80 to 95 per cent with no visible loss.

Do these tools upload my images anywhere?

No. Every image tool here runs entirely in your browser using the Canvas API. Your photo never touches a server. You can disconnect from the network and the resizing, conversion and compression still work. That is the entire reason these exist.

What dimensions does Instagram, LinkedIn or Twitter want?

Instagram feed: 1,080 x 1,080 (square) or 1,080 x 1,350 (portrait). Stories: 1,080 x 1,920. LinkedIn feed: 1,200 x 627 for link previews, 1,200 x 1,200 for shared images. Twitter/X: 1,200 x 675 for link cards, 1,200 x 1,200 for posts. The Photo Resizer lets you crop to any of these.

What is the difference between WebP and AVIF?

WebP (2010, Google) is universally supported and produces files about 25 to 35 per cent smaller than JPG at the same quality. AVIF (2019, AOMedia) goes further: another 20 to 30 per cent smaller again, but encoding is slower and the format is newer. For new web work in 2026, AVIF if you have an encoder; WebP as a safe default.

Why in-browser image tools are safer than online ones

Most "free online image resizer" websites work by uploading your photo to their server, resizing it there, and handing it back. That means every holiday snap, product shot, or ID document you resize sits temporarily on someone else's machine. Some keep copies. Some train models on them. Some have been breached. Even the honest ones are an extra hop through the public internet.

A browser-only tool does the same job in the tab you are already looking at. The image is decoded, resized on an HTML canvas, and re-encoded, all on your own device. Nothing is sent anywhere. If your Wi-Fi dropped while you were resizing, the tool would still work.

When to resize, when to compress, when to convert

Resizing changes the pixel dimensions of an image: a 4000×3000 photo becomes, say, 1200×900. That alone usually cuts the file size dramatically. Compressing changes how aggressively the image is encoded at a given size: a JPEG at quality 90 is a different file from the same image at quality 70, even at identical dimensions. Converting swaps the format: PNG to JPEG for photos, PNG to WebP for near-lossless-but-smaller, JPEG to PNG for screenshots with flat areas.

The Photo Resizer does all three at once, so you can see the effect of each choice on the final file size.