Windows Desktop Utility
JSON Medic repairs malformed and invalid JSON locally, privately, with no cloud uploads. Drop a broken file in, see every problem categorized by severity, fix it in one click.
The Problem
JSON comes out of APIs, config editors, export tools, and hand-edited files looking nothing like what the parser expects. Trailing commas that work in JavaScript but not in JSON. Single-quoted strings. Inline comments. Unquoted keys. Unclosed brackets that trace back to a field 200 lines up.
Debugging a broken JSON file by hand means scrolling through thousands of lines, counting braces, and guessing which character on which line triggered the parse error. A validator tells you the line where the parser gave up - not the line where the actual problem is.
JSON Medic does not just validate. It reads every byte, identifies every problem, and applies the right fix for each one - without guessing and without corrupting structure that is already valid.
Fixes trailing commas before closing brackets and braces, missing commas between elements, unmatched or unclosed brackets, and misplaced colons. The most common class of breakage from hand-edited files and JavaScript-origin exports.
Replaces JavaScript-only literals - undefined, NaN, Infinity - with valid JSON equivalents. Converts single-quoted strings and unquoted keys to double-quoted. Strips inline comments in both // and /* */ form.
Removes BOM markers that silently break JSON parsers. Fixes invalid Unicode escape sequences and malformed surrogate pairs. Detects and resolves duplicate keys. Repairs escaped character errors that pass the eye test but fail the parser.
See It Work
A hand-edited config file comes in with JavaScript-style comments, a trailing comma, a single-quoted string, and an undefined value. JSON Medic identifies every issue and repairs them in a single operation.
Large File Mode
Files over your configured threshold activate large file mode automatically. JSON Medic analyzes and repairs the full file on a background thread while the UI stays completely responsive.
Built-in Presets
Presets apply a curated combination of repair passes in one click. Select a preset, adjust anything you need, then repair. Save your own configuration as a profile and reload it the next time the same broken format arrives.
Profiles are plain JSON - version control them alongside the pipelines that consume the repaired output.
Privacy and Local Operation
JSON files contain API credentials, user records, configuration secrets, and internal system state. JSON Medic processes everything locally. There is no cloud component, no account, and no network access during repair.
Contact UsRecurring File Formats
If you receive the same malformed JSON from a legacy API, a vendor system, or an internal export tool on a recurring schedule, configure the repair once and save it as a profile.
Who Uses JSON Medic
Debugging malformed API payloads, repairing hand-edited config files, and cleaning up JSON exports from legacy systems. Faster than manually counting braces across 3,000 lines.
Infrastructure config files, CI/CD pipeline definitions, and deployment manifests broken by a hasty edit. JSON Medic finds the problem and fixes it without corrupting the structure around it.
Cleaning JSON feeds and export files before ingestion into data pipelines, databases, or analytics platforms. Handling encoding garbage and structural damage before the transformation work starts.
Pricing
No subscription. No recurring fee. Buy once, use on your machine for as long as you want. Free updates through v1.x.
JSON Medic is available exclusively through the Microsoft Store. The Store handles purchase, installation, and automatic updates.
Questions - visit our support page
Purchased and installed through the Microsoft Store. Automatic updates included.