Melt guide

Compress an image right from Finder on Mac

Right-click → compress. macOS sort of supports this. Here's what works, what doesn't, and the faster way.

4 min read

You want to right-click an image in Finder, hit “Compress,” and have a smaller file. Reasonable ask. macOS partially supports it — it’s just not labelled compression.

The native way

Right-click the image → Quick Actions → Convert Image. You’ll get a small dialog with two options:

This uses macOS’s built-in image pipeline (the same one Preview and sips use). Pick HEIF for the smallest output, JPEG for the broadest compatibility. The “Image Size” presets correspond to roughly 640px / 1280px / 1920px / original on the longest edge.

It works. The catches:

For most quick jobs, this is genuinely fine. If you’ve never noticed it before, give it a try — right-click an image right now.

Adding a custom Quick Action

If you want a Finder right-click that runs at your settings, build one with Automator:

  1. Open Automator → New → Quick Action.

  2. Set “Workflow receives” to “image files” in Finder.

  3. Drag in a “Run Shell Script” action.

  4. Paste:

    for f in ”$@”; do sips -s format jpeg -s formatOptions 80 -Z 2000 “$f” —out ”${f%.*}-small.jpg”; done

  5. Set “Pass input” to “as arguments.”

  6. Save as “Compress to 2000px JPEG.”

Now it appears under Quick Actions in Finder’s right-click menu. You can build several — one for screenshots, one for web exports, one for email size — each with different settings.

The faster way

If you don’t want to build Automator workflows, Download Melt. It doesn’t add a right-click action, but it sits in your dock and accepts dragged files from anywhere.

  1. Download Melt and pin it to the dock.
  2. From Finder, drag any image (or selection of images) onto the Melt icon.
  3. Adjust settings if needed.
  4. Click Compress.

For a Finder-centric workflow, dragging onto a dock icon is about the same number of clicks as Right-click → Quick Action — and you get real control over quality, format, resize, and EXIF in the same gesture.

How much smaller will it really get?

Quick Action with HEIF: 50-70% smaller than the original JPEG. Quick Action with JPEG: 40-60%. Automator + sips at quality 80: similar to Melt at quality 80, which is 60-85% for PNG and 50-70% for JPEG.

Honestly, the right answer depends on how often you do this. For weekly compressions, Quick Action is enough. For daily, build the Automator workflow or grab a real tool.

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