JASON (JSON Manager)

Tracking since Apr 1, 2026.

Changelog

• Apr 20, 2026
  description

  JASON gives you a powerful JSON editor right in your browser sidebar - the coolest spot to paste your JSON snippets.
  
  Save up to 20 named snippets across tabs with syntax highlighting, line numbers, and live validation.
  Format to pretty print or minify to a single line in one click. Collapse and expand nested blocks instantly. Everything is saved locally, no network requests, no tracking, no data leaving your browser.
  
  1.1.2 release notes
  - Fixed an issue where pasting JSON after clearing the editor could duplicate content.
  - Improved paste handling so a single paste event is processed once, preventing accidental repeated insertion.
  
  What's new in v1.1.0
  
  Collapse All / Expand All nested blocks
  Drag and drop to reorder tabs
  Duplicate any tab in one click
  Undo / redo up to 50 steps
  Download snippets as JSON files
  Real time file size indicator
  Light and dark theme
  Keyboard shortcuts for all main actions
  
  Whether you're troubleshooting API payloads, inspecting partner requests, or just need a persistent place to manage your JSON.
  JASON keeps everything organised and always within reach.

  JASON (JSON Manager) is a local-first JSON workspace that lives in your browser sidebar and is built for developers, QA, API testers, and technical users who work with JSON all day.
  
  **What is it**
  A focused side-panel tool for:
  - Collecting JSON-like payloads from active pages,
  - Storing and organizing snippets in tabs,
  - Validating/formatting/minifying content,
  - Comparing two payloads with visual diff guidance.
  
  **How you use it**
  Three core modes:
  - Store: 
    - tabbed JSON workspace (edit, search, fold, format, save, download).
  - Compare: 
    - two JSON fields side by side, run comparison, inspect line/word-level diffs, and confirm perfect matches.
  - Capture: 
    - run scan on current tab, review results, store or compare selected captures.
  
  **Why**
  - Reduces context switching between devtools, editors, and scratchpads.
  - Keeps JSON workflows in one persistent place.
  - Improves review speed with inline compare visuals and searchable content.
  
  **UI/UX**
  - Local persistence with fast reopen behavior.
  - Light/dark theme support.
  - Real-time size/validation feedback.
  - Search across workspace content and capture content.
  - Scan flow includes user feedback and retry behavior for common tab-readiness timing cases.
  
  **Privacy and architecture**
  - No analytics, no third-party telemetry, no external data transmission.
  - Data stays in browser local storage.
  - Plain JS architecture with shared source + browser-specific manifests/background scripts.
  - Deterministic build pipeline with manifest sync checks.

• Apr 20, 2026
  host_permissions

  (empty)

  <all_urls>

• Apr 20, 2026
  permissions

  sidePanel, storage

  sidePanel, storage, tabs, scripting

Permissions & access

Permissions

sidePanelstoragetabsscripting

Host access

<all_urls>

Screenshots

Similar extensions

Alternatives to JASON (JSON Manager), ranked by description similarity.

JSON Formatter - Viewer & Beautifier

Format, view, and beautify JSON data with syntax highlighting, collapsible tree view, and search. Works on any page.

1

Json Ninja

Parse and format JSON with syntax highlighting

9

★ 5.0

Markdown & JSON Editor

Edit Markdown & JSON files in Chrome with live preview, themes, formatting tools, and tree view.

30

JSON Formatter

Format JSON with syntax highlighting, line numbers, and full-size mode. Sleek dark theme and intuitive interface.

20

JSON Formatter & Viewer

A Chrome extension that detects, formats and visualizes JSON on web pages.

88

★ 5.0

JSON Swiss

JSON Swiss - Ultimate Multi-Tool! Json format,pretty,edit,grid view, convert to XML/YAML/CSV...,generate Python/Java/C#... code.

6

Sunset JSON Tools

Validate, format, and minify JSON instantly. Sunset-themed UI. Copy result with one click.

—

JSON Formatter

Format, validate, and beautify JSON instantly! Pretty print, minify, and validate JSON with syntax highlighting.

12