Jace - JSON Editor

JSON files, finally friendly

Only for Mac

Free

Mac

New in 1.1: semantic compare shows which keys and values actually changed — plus multi-node selection, drag-to-reorder tree editing, and a faster launch screen. Explore JSON as a tree, edit the source beside it, and compare two documents to see exactly what changed — with search, formatting, parse feedback and Quick Look. Jace makes JSON viewing and editing a breeze. An interactive tree and a syntax-highlighted source editor stay side by side, so you can understand a document, make changes, and keep your place without switching views. COMPARE, SEMANTICALLY • Compare the open document with a file, your clipboard, or pasted text • Differences are matched by key and value, so you see real changes rather than shifted lines • Counts and filters for added, removed and changed, with a navigator for the whole hierarchy • Inspect both sides of a difference together, with the JSON path ready to copy • Decide whether object property order counts; arrays are always compared by position • Start a comparison from the launch screen without opening a document first EXPLORE AND EDIT • Expand and collapse objects and arrays • Edit keys, strings and numbers directly in the tree, and toggle booleans with a click • Duplicate, sort or remove any node, and drag nodes to reorder them or move them elsewhere • Select several nodes with ⇧-click or ⌘-click and remove them together, as one undo step • Select a tree node to jump to its source, or place the cursor in the source to highlight the matching node FIND AND FORMAT • Search across keys and values, with matches highlighted and a count you can step through • Prettify or minify from the toolbar or with keyboard shortcuts • Choose your indentation width and editor font size • See line numbers, syntax highlighting, document size, line count and JSON parse status BUILT FOR REAL-WORLD FILES • Use familiar macOS document workflows for opening, editing, saving and undoing changes • For documents 50 MB and larger, Jace switches to a dedicated large-file mode for smooth interactions • Keep recent files and in-progress drafts within reach • Preview .json files from Finder with the included Quick Look extension Jace stays focused on one job: helping you read, change and compare JSON without losing sight of its structure. Open a file and get to work — no account or workspace setup required.

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Jace 1.1 adds semantic comparison, hands-on tree restructuring, and a faster way to start. SEMANTIC COMPARE • Compare the open document against a file, your clipboard, or pasted text • See which keys and values actually differ — not which lines moved • Added, removed and changed counts, with a filter for each • Step through differences or jump straight to one in the navigator • Inspect both sides of any difference, with its JSON path ready to copy • Duplicate keys are matched by occurrence, so nothing is silently merged • Choose whether object property order counts; arrays are always compared by position • Compare two inputs from the launch screen, without opening a document first RESTRUCTURE IN THE TREE • Select several nodes with ⇧-click or ⌘-click, then remove them in a single undo step • Selecting a container takes its whole subtree with it, so nothing is half-deleted • Drag a whole selection into a new position • Duplicate, sort or remove any node from its context menu • Sort children by key or by value, ascending or descending — or recursively • Drag nodes to reorder them, or to move them into another object or array • Every change is a normal undo step, and the source updates with it A FASTER START • New launch screen: start a draft, turn the clipboard into one, open a file, or compare • Search now lives in the tree pane, with a match count and quick stepping between hits REFINEMENTS • Liquid Glass materials on macOS 26, with the earlier appearance on older systems • Smoother transitions moving between editing, comparing and searching • Jace now requires macOS 15 or later

The developer, Shao-Yu Liang, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Linked to You

    The following data may be collected but it is not linked to your identity:

    • Location
    • Identifiers
    • Usage Data
    • Diagnostics

Privacy practices may vary, for example, based on the features you use or your age. Learn More

The developer has not yet indicated which accessibility features this app supports. Learn More

Seller
  • Shao-Yu Liang
Size
  • 2.9 MB
Category
  • Developer Tools
Compatibility
Requires macOS 15.0 or later.
  • Mac
    Requires macOS 15.0 or later.
Age Rating
4+
Copyright
  • © 2026 Andy Liang