Compress, resize and convert images in bulk
Batch-compress JPEG/PNG/WebP, resize by pixels, percent or preset, convert formats, and export social-media sizes — all offline on your Mac.
Compress, resize and convert images in bulk with 1FileTool — drop a folder of photos and every image is processed locally on your Mac. The Image Tools group also accepts HEIC input everywhere.
Protect your originals first
Replace source is ON by default: the output overwrites the original file and no backup is kept. Before following along, open Settings › General and turn Replace source off, or pick a separate output folder.
Compress images
Image Tools › Compress (tool page) re-encodes each file to be smaller:
- JPEG is re-encoded with MozJPEG — the quality control trades detail for size.
- PNG compresses losslessly at maximum level — pixel-identical output, smaller file.
- WebP re-encodes at the chosen quality.
- GIF converts to an animated WebP.
If a re-encoded file would come out bigger than the original, the tool keeps the original — a compress run never makes a file worse.
Resize three ways
- Resize (pixels) — type a Width, Height, or both. The hint reads "Leave one side empty to keep the aspect ratio." (Resize)
- Resize % — a segmented control with 25%, 50%, 75%, 150% and 200%. (Resize by percent)
- Resize (preset) — Thumbnail, HD, Full HD or 4K for common targets. (Resize presets)
Convert formats
Image Tools › Convert (tool page) offers JPEG, PNG and WebP as output. Camera orientation stored in EXIF is applied during conversion, so rotated photos come out the right way up. HEIC input works here too — see HEIC to JPG.
Social media sizes
Social Media Resize (tool page) exports one file per platform you pick — Instagram post, Instagram story, Facebook cover, X header, LinkedIn banner and YouTube thumbnail — cropped to fill each platform's exact dimensions.
Batch behaviour
Every tool on this page takes a dropped folder: one result card per file, a per-file saving (compress) or new dimensions, and the run can be cancelled partway through.
Try it in your browser
This tool also runs in the browser. Try it here first, then do a whole folder at once in the app.
Try Compress Online
Real Browser ProcessingNo files selected
Original
Result
Processing happens locally in your browser. The desktop app adds more formats, better performance on very large files, and advanced automation.