CSV ⇄ JSON Converter
Text & Code Tools100% Private · In-BrowserConvert CSV to JSON and back with an RFC-4180-safe parser — quoted fields, embedded commas and newline traps all handled.
Loading tool…
Key features
- CSV → JSON with a strict RFC-4180 state-machine parser: quoted fields, escaped quotes ("") and commas or newlines inside quotes stay literal.
- Delimiter selector for comma, semicolon, tab or pipe inputs.
- CSV options: treat first row as header (otherwise column_1, column_2…), trim whitespace per cell, and auto-detect types (42 → number, true → boolean, empty → null).
- Type detection keeps leading-zero strings like 007 as text, so IDs and ZIP codes don't get mangled.
- JSON → CSV accepts arrays of flat objects (union of all keys becomes columns) or arrays of arrays, with an include-header switch.
- Ragged rows produce explicit warnings (row number, fields found vs expected) and downloads as .json or .csv.
How it works
Pick the direction
Use the CSV → JSON tab for spreadsheet data, or JSON → CSV to flatten API results back into rows.
Paste the input and set options
Paste data on the left, choose the delimiter, and flip the header/trim/type switches to match your source. Output updates live (with a short debounce for big pastes).
Check warnings and stats
Ragged rows are called out by row number instead of silently padded; tiles show row count, column count and output size.
Copy or download
Copy the result, or download it as dailywebtools-converted.json / dailywebtools-converted.csv. The Load sample button demonstrates tricky quoting in one click.
Tips for better results
- The sample CSV deliberately includes a comma inside a name, escaped quotes and a value spanning two lines — use it to verify your own tricky files.
- Disable auto-detect types if you need every cell to stay a string, e.g. when product codes must remain text.
- Duplicate header names are allowed; the later column wins the key — rename headers first if that matters.
- JSON → CSV requires every item to be a flat object or an array; nested objects are stringified rather than exploded into columns.
Frequently asked questions
More Text & Code Tools
View all →Explore all 86 tools
Image, PDF, text, calculator and media utilities — all free, all private, all running right in your browser.
Browse the complete toolkit