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Making files smaller

3 min read

Mochi makes files smaller, and converts them from one format to another. Copy an image and the copy on your clipboard is already smaller. Drag any file and a small plate slides in, offering to shrink it, resize it, or convert it.

The four ways in

DoorHow it works
Copying an imageThe copy on your clipboard is rewritten smaller, automatically, before you paste it
Dragging a fileA plate slides in at the edge of the screen. Drop the file on Squish, Convert or Downscale
The search windowType squish, convert or downscale and press
Keyboard shortcutsAn opt-in group in Settings > Hotkeys — see below

Copied images

When you copy an image, Mochi re-encodes the copy on your clipboard in the background — typically to a fraction of the size, in about a tenth of a second. A full-screen screenshot usually comes back around 80% smaller, looking the same. What you paste is the smaller version; nothing else changes.

  • Images copied out of an editor are left alone — re-encoding something you are still editing would quietly stack up quality loss.
  • Files that are already small or already lean are skipped rather than churned.
  • If the pasteboard changes while Mochi is working, the result is thrown away rather than pasted over something newer.
  • One switch in Settings > Squish turns it off.

The drop plate

Start dragging a file — from Finder, your desktop, anywhere — and the plate slides in from the edge of the screen. Drop the file on a slot and Mochi puts the result next to the original. It needs no permission, it never appears for a file it cannot act on, and it stays out of the way of whatever you are dragging.

What comes out

  • The result is a new file next to the originalshot.png becomes shot-squished.png. Your original is never written over.
  • If the smaller version is not actually smaller, you keep the original. Mochi never hands back a bigger file and calls it a win.
  • Transparency is never flattened, animation frames are never dropped, and a file's extension is never changed without being asked.

What it can convert

FamilyInOut
ImagesPNG, JPEG, HEIC, TIFF, GIF, BMP, WebP, AVIF, most RAWPNG, JPEG, HEIC, TIFF
AnimationsGIF, APNGGIF, APNG, or a much smaller MP4
VideoMP4, MOV, M4V and anything QuickTime playsMP4, MOV, a GIF, or just the audio
AudioMP3, M4A, WAV, AIFF, FLAC, ALAC and moreM4A, WAV, AIFF, FLAC, ALAC
DocumentsWord, RTF, HTML, Markdown, plain textPDF, RTF, HTML, plain text
PDFPDF, or several imagesA smaller PDF, an image per page, or one PDF from the images

Free and Pro

Images are free with no limit — the automatic clipboard squish, the plate, downscaling and image-to-image conversion. Pro adds video and audio, documents and PDF, and several files at once. See what Pro includes.

Keyboard shortcuts

One opt-in group in Settings > Hotkeys works the clipboard without touching the mouse. It ships switched off, like the window snapping keys.

After switching the group on.

S

Squish the image on your clipboard

Downscale the image on your clipboard

Z

Put the original back