JSON・CSV・XML・YAML conversion tool

Overview #Personal Development

A local-first web productivity tool for assembling syntax verification, field name mapping, type conversion, extraction, and format conversion that occur during data integration between different systems in a single screen. Rather than simple data formatting, it is designed around reusable configurations as conversion templates.

Main Features

• 4 Format Support: Mutual conversion and validation of JSON, CSV, XML, and YAML
• Automatic Format Detection: Auto-detects format from input data, with manual selection available if misdetected
• Conversion Pipeline: Build Flatten, key mapping, filtering, type conversion, and field selection in ordered Steps
• Multiple Views: Simultaneously view code editor, data tree, table, and conversion builder
• Syntax Diagnostics: Display errors in detail by line, column, and reason
• Diff Verification: Track differences before and after conversion
• Template Saving: Save conversion settings to browser and reuse with new data
• Local Processing: All processing completes within the browser; input data is not sent to server

Target Users

• Personnel responsible for data migration and system integration
• Developers performing API verification and operational maintenance
• Business users handling data with different key names and hierarchical structures

Technical Characteristics

• Fully processed within browser (local-first)
• Large data (200KB or more) processed with Web Worker
• Input data body is not saved; only template settings are saved
• Security measures implemented such as DOCTYPE rejection for XML