Data tools

Base64 Encode/Decode (Text & File Support)

Use one screen for Base64 decode, Base64 encode, and quick conversion.

CSV Deduplicator (Remove Duplicates by Key Columns)

Remove duplicate rows from CSV by selected key columns. Choose first-win, last-win, or merge non-empty values for practical deduplication.

CSV Editor (Preview, Remove Columns, and Re-download)

Inspect first, then edit. Remove unnecessary columns, tidy your data, and download a new CSV.

CSV to JSON Converter (Header Row to Keys)

Convert CSV into a JSON array. Paste or upload a file, processed locally by default.

CSV/TSV Converter (Batch Delimiter Conversion)

Convert CSV and TSV (comma ↔ tab) in one click. Quoted fields and multiline cells are handled safely.

JSON Formatter & Minifier

Pretty-print or minify JSON and pinpoint errors with line and column details.

JSON Key Sorter (Stable Key Order for Cleaner Diffs)

Automatically standardize JSON key order to make reviews and comparisons easier.

URL Encode/Decode (Japanese URL & Query Converter)

Convert URL encode/decode (percent encoding) instantly in your browser. Switch between encodeURIComponent/encodeURI behavior and detect possible double encoding.

YAML ↔ JSON ↔ TOML Converter (Mutual Conversion, In-Browser)

Convert YAML, JSON, and TOML both ways. Paste text and get formatted output instantly.