The best image compressors for Mac in 2026

There are more good ways to shrink images on a Mac than ever — free and paid, apps and web tools. Here's an honest rundown of the ones worth knowing, what each is best at, and which one to pick for the way you work.

Disclosure: we make TinyPresso, so we're biased. We've tried to describe every tool fairly — including where another one is the better choice. Details checked October 2026.

Quick picks

What we looked at

• How much smaller files get — and whether they still look the same.
• Privacy — does the tool upload your images, or work on your Mac?
• Batches — can you drop in a pile of images at once?
• Modern formats — can it handle iPhone HEIC photos and convert to WebP or AVIF for the web?
• Effort — sensible results without fiddling with settings.

1. TinyPresso — compress and convert in one drop

TinyPresso is a native Mac app built around one idea: drop images in, get much smaller copies out, without anything leaving your Mac. It removes color detail your eyes can't tell apart, which is where the big savings come from. In our tests a 2.3 MB portrait PNG came out at 734 KB (−69%), a 2.4 MB landscape at 676 KB (−72%), and a Retina screenshot went from 875 KB to 261 KB (−70%).

It also converts between PNG, JPEG, HEIC, AVIF and WebP in the same step — that same screenshot saved as WebP was just 94 KB. You can paste images straight from the clipboard with ⌘V, and if a file can't get any smaller, the original is kept instead of writing a bigger copy.

Good to know: it's free to use, with extended abilities available via subscription or a one-time purchase. Requires macOS 14 or later.

2. ImageOptim — the free classic

ImageOptim has been the default answer for years, and for good reason: it's free, open source, and simple. By default it's lossless — every pixel stays exactly the same — and it strips hidden extras like camera details and GPS location. You can turn on lossy compression in its settings for smaller files.

Good to know: it works on PNG, JPEG, GIF and SVG, and doesn't convert to newer formats like WebP, AVIF or HEIC. Lossless mode keeps quality perfect, but the savings are usually modest. See our ImageOptim alternative comparison.

3. Squash — a polished all-rounder

Squash from Realmac Software is a well-designed Mac app that opens a long list of formats — including HEIC, PSD and RAW photos — and can save to JPEG, PNG, WebP and AVIF. A good pick if you want one app that accepts almost anything you throw at it.

4. Compresto — images, video and PDFs

Compresto is a paid Mac app that compresses videos and PDFs as well as images. If you regularly need to shrink screen recordings or documents too, having it all in one place is the main draw.

5. Zipic — automatic folder compression

Zipic's standout feature is watching folders: point it at your screenshots or design-export folder and new images get compressed automatically. Handy if you'd rather never think about compression at all.

6. Clop — clipboard optimizer

Clop sits in your menu bar and optimizes images (plus videos and PDFs) as you copy them. It's great for people who paste screenshots into chats and docs all day.

7. Squoosh — best for one image at a time

Squoosh is Google's free web app. It runs inside your browser, so images aren't uploaded, and its side-by-side slider with detailed quality settings is excellent for fine-tuning a single hero image. The catch: it handles one image at a time. More in our Squoosh alternative page.

8. TinyPNG — the famous web tool

TinyPNG made smart PNG compression mainstream and works on any computer with a browser. Your images are uploaded to their servers, and the free web version limits how many images and how large a file you can do at once. Paid plans and a developer API are available. See TinyPNG alternative for Mac.

9. Preview — already on your Mac

Preview's File → Export… gives you a quality slider for JPEG and HEIC, which is fine for the occasional photo. It has no real compression for PNG and doing batches is clunky — but it costs nothing and needs no install.

Which one should you pick?

• You want big savings, batches and format conversion, all offline: TinyPresso.
• You want free, open source and strictly lossless: ImageOptim.
• You also compress videos and PDFs: Compresto or Clop.
• You want compression to happen automatically in a folder: Zipic.
• You're perfecting one image for a website: Squoosh.
• You're not on a Mac: TinyPNG or Squoosh.

Related guides

• How to reduce image file size on a Mac
• How to compress PNG files on a Mac
• Compressing images for the web

FAQ

What is the best free image compressor for Mac?

ImageOptim is the best-known free and open-source option, and it is lossless by default. TinyPresso is also free to use and adds bigger savings plus conversion to WebP, AVIF and HEIC, all offline.

Can I compress images on a Mac without uploading them?

Yes. Native Mac apps such as TinyPresso and ImageOptim compress images on your Mac, so nothing is uploaded. Web tools like TinyPNG upload your images to their servers.

Does compressing an image reduce its quality?

Good compressors remove only detail your eyes can't tell apart, so the image looks the same while the file gets much smaller. Lossless tools change no pixels at all, but usually save less.