Complete PicCaddy Guide

PicCaddy does more than convert PNG to JPG. It separates everyday image work into clear actions: batch conversion from Finder, focused editing, target-size compression, folder browsing and cleanup, and optional automation for clipboard images and newly added files.

The main processing stays on the Mac. PicCaddy requires no account, does not upload images to a developer server, and does not depend on external analytics, payment, cloud storage, or AI services.

Features and entry points

Feature	Typical use	Where to start
PNG to JPG	Reduce screenshots, photos, and web assets in batches	Finder, drag and drop, or Choose PNG Images
Image editing	Crop, resize, rotate, and annotate	Finder Image Tools or Edit Images
Background removal	Create a transparent PNG around a subject	Finder Image Tools
Image compression	Limit each file's size and longest edge	Finder Image Tools or Compress Images
Image browser	Review a folder with zoom and full screen	Choose a folder in Image Browser
Image cleanup	Filter candidates by size, date, dimensions, and format	Choose a folder in Image Cleanup
Clipboard monitoring	Replace copied large PNG image data with JPG	Settings → Clipboard
Folder monitoring	Process new large PNG files in one directory	Settings → Folder
Conversion history	Review outcomes and export reports	Settings → History

Batch-convert PNG files from Finder

After installing PicCaddy and enabling its Finder extension, select one or more PNG files, open the context menu, and choose Convert to JPG. New JPG files appear beside the sources. Existing names receive a number, so earlier files are never overwritten.

PNG supports transparency; JPG does not. Transparent pixels are placed on a white background during conversion. Keep PNG for icons, interface assets, and anything that still needs transparency. JPG is usually more appropriate for photos, large screenshots, email attachments, and web images.

Image Conversion settings apply to generated JPG files:

• Longest edge: images above the limit scale down proportionally without stretching;
• Maximum file size: PicCaddy adjusts JPG quality first, then reduces pixel dimensions if necessary.

You can also drag a PNG into the home window or choose PNG Images and select an output folder. Manual conversion always preserves the source.

Crop, resize, rotate, and annotate

The editor opens one or more PNG or JPG files. Crop by dragging a region and refining its corners. Resize preserves the aspect ratio. Rotation works in 90-degree steps to the left or right.

Annotation tools include text, arrows, rectangles, and numbered markers. Text boxes can be moved and resized. Drag to draw an arrow or box, or choose a number and click to place a step marker. Annotations support colors, selection, Delete, and Undo. Preview zoom changes only the on-screen view, and Reset restores the current image to its initial state.

Saving creates a new file with an edited suffix and never overwrites the source. If macOS has not granted write access to the source folder, choose that folder or another destination. PicCaddy stores the authorization and restores the selected save location for later edits from the same source directory.

Remove an image background locally

On macOS 14 or later, select PNG or JPG files in Finder and choose Remove Background under Image Tools. PicCaddy uses Apple Vision locally to identify foreground subjects and generate transparent PNG files.

Outputs receive a background-removed suffix and automatic numbering. Originals remain unchanged. Clear subject boundaries and visible foreground-background contrast usually work best; hair, glass, reflections, and similar colors deserve close inspection. When no foreground can be identified, PicCaddy reports a failure and preserves the source.

Check important transparent results against both light and dark backgrounds. Open the output in the editor when it also needs cropping, rotation, resizing, or annotations.

Compress images to a target size

Compression accepts one or many PNG and JPG images. Set a maximum size per output, an optional longest-edge limit, and the output format. The preview estimates before-and-after sizes for the current image.

The file-size target applies separately to every output. PicCaddy adjusts JPG quality first and scales pixel dimensions only if the result remains too large. Images with identical dimensions can compress differently because texture and detail affect encoded size.

Preserve Format keeps PNG where transparency matters. Convert to JPG can use white, light gray, or black for transparent regions. Additional options can skip sources already below the target, remove camera and location metadata, and cap the longest edge.

Compressed files are saved beside the originals with a compression suffix. Sources are always preserved, and the completion view reports generated, skipped, and failed items plus total storage saved.

Browse images in a folder

Choose Image Browser from the home window and select a folder. The browser reads only that folder's first level and does not scan subfolders.

Move between images, zoom, fit the image to the window, or enter full screen. Double-click toggles fit and original size. Left and right rotation change the current preview; use the editor when a rotated result must be saved. The current image can also be opened for editing or moved to Trash after confirmation.

Filter and clean an image folder

Image Cleanup also stays in the selected folder's first level. It displays file name, pixel dimensions, file size, modification date, and a preview. Search supports file names and pinyin or initials for Chinese names.

Filters can combine file-size ranges, longest edge, width or height, calendar dates or recent time periods, formats, landscape or portrait orientation, and selected or unselected state. For example, combine PNG, larger than 5 MB, and a longest edge above 3000 pixels to find oversized screenshots.

Click an item for a preview or press Space for macOS Quick Look. Select Current Results affects the visible filtered set. Previously selected hidden items remain selected, and the final confirmation reports hidden selections, item count, total size, and folder.

Confirmed files move to the macOS Trash and remain recoverable until the Trash is emptied. PicCaddy verifies that every target still belongs to the selected directory.

Automatically convert large clipboard PNG images

Enable clipboard monitoring and select a size threshold in MB. PicCaddy checks PNG image data and converts only content above that threshold. macOS may request clipboard permission the first time readable image data appears.

This feature handles image data copied from a browser, screenshot tool, or editor. Copying a .png file in Finder puts a file reference on the clipboard, so PicCaddy leaves the file and disk content unchanged.

Copying the same image again can trigger another conversion because each new system clipboard change is checked. PicCaddy recognizes its own JPG write-back and does not process the same event repeatedly.

Optional notifications report size reduction. The clipboard log retains up to 200 events and stays below 256 KB. It stores time, sizes, and outcome, never image content.

Watch a folder for new PNG files

Choose and authorize one folder in Folder settings. PicCaddy processes a file only when it is a new PNG in that folder's first level, arrived after monitoring began, exceeds the selected threshold, and has finished writing. Existing files and subfolders remain untouched.

Folder conversion uses the longest-edge and maximum JPG size settings from Image Conversion. Results appear beside their sources and receive automatic numbering for name conflicts.

PNG and JPG are both preserved by default. When Delete Original After Successful Conversion is enabled, PicCaddy first saves the JPG, verifies that the PNG remains the same unchanged regular file, and only then deletes it. Conversion, save, source-change, or deletion failures leave the PNG in place. This removal does not move the PNG to Trash, so test with replaceable images before enabling it.

Folder authorization and monitoring settings can be restored after relaunch. PicCaddy runs as a single instance, preventing duplicate monitors. Enable launch at login in General settings when monitoring should resume after signing in.

Review history and export reports

History combines Finder, Clipboard, and Folder events. A record can include time, source, successful, skipped, or failed outcome, file name, before-and-after sizes, storage saved, duration, and an error explanation. Clipboard data without a disk name appears as Clipboard Image.

Filter the last 7 days, 30 days, or all time, then combine source, outcome, and file-name search. Summary cards show record count, success rate, storage saved, and average duration. Charts show daily volume, event count by source, and storage savings by source.

The local database retains up to 10,000 recent events, while the table displays up to 500 rows. CSV export contains every record matching the active filters for further analysis. PDF export includes filter details, summary numbers, charts, and recent events.

History and reports contain no image content, thumbnails, full file paths, or unrelated clipboard content. Exports are saved only to the location you choose.

Permissions, privacy, and a practical starting point

PicCaddy uses the macOS App Sandbox. It can access only files and folders you select. Folder access that must survive a relaunch is stored with macOS security-scoped bookmarks. Image processing, foreground recognition, statistics, and report generation all happen locally.

Start with manual Finder conversion and inspect JPG quality before setting automation thresholds. Preserve important originals, transparency assets, and files that still need editing. Enable source deletion only for a tested folder that should contain converted JPG files alone.