FinderBuddy
Right-click file tools for Mac, built into Finder
Paid
Productivity
Tag
Image converter tools change a picture from one form into another. The three here take very different routes.
FinderBuddy is a native Mac app. It adds image conversion and compression to the Finder right-click menu, and it costs a one-time $9 at launch for up to 3 Macs. ihateimg.cv runs 58 free tools in the browser and keeps files on the device, with no account or watermark. ImageToBeads converts a photo into a Perler or Hama bead pattern, and it is free with PNG export.
3 tools
Right-click file tools for Mac, built into Finder
Turn photos into editable Perler bead patterns for free
Image tools that never upload your files