CSV Formatter
FormattersParse, preview and convert CSV and TSV. Auto-detects delimiter, renders a searchable sortable table, exports to JSON with tree/graph views, and downloads as Excel.
About CSV Formatter
The CSV Formatter is a pure-JavaScript, browser-based tool that parses, previews, and converts CSV and TSV data without any server round-trips. It automatically detects the delimiter (comma, semicolon, tab, or pipe) from the first 2000 characters of input, renders the data as a searchable, scrollable table, and can export the result as formatted CSV, a JSON array (with interactive tree and D3 graph views), or an Excel (.xlsx) file. A full RFC 4180-compliant CSV parser handles quoted fields, escaped double-quotes, and multi-line cell values. Your data never leaves the browser.
Features
- ✓Auto-detects delimiter: comma, semicolon, tab (TSV), or pipe from the first 2000 characters
- ✓RFC 4180-compliant CSV parser: handles quoted fields, escaped double-quotes, and multi-line cells
- ✓Table view: rendered as a searchable, horizontally scrollable grid with a live filter input
- ✓Toggle first-row header detection on or off
- ✓Export to formatted CSV with correct quoting and chosen delimiter
- ✓Export to JSON array — each row becomes an object keyed by header names
- ✓JSON mode: interactive Tree View and D3-powered Graph View for exploring data structure
- ✓Export graph as SVG (vector) or PNG (raster)
- ✓Export to Excel (.xlsx) via the xlsx library — preserves headers and all filtered rows
- ✓Syntax-highlighted editor for raw CSV input and CSV/JSON output
- ✓One-click clipboard copy of CSV or JSON output
- ✓Real-time byte-savings stats (input vs output size)
- ✓Language picker — instantly switch to JSON, YAML, or 20+ other formatters
- ✓Mobile-responsive layout
- ✓100% client-side — your data never leaves the browser
Common Use Cases
- Quickly previewing CSV exports from databases before importing them elsewhere
- Converting CSV data to JSON for use in REST API payloads or configuration files
- Searching and filtering large CSV files in the browser table view without Excel
- Detecting and correcting delimiter issues in TSV or pipe-delimited exports
- Exporting filtered CSV subsets as properly formatted files
- Visualising CSV data relationships as a JSON graph for exploratory analysis
- Downloading CSV data as a formatted Excel file without a spreadsheet application
- Sharing readable CSV previews in code reviews or data engineering discussions
Frequently Asked Questions
QWhich delimiters does the auto-detect support?
Comma (,), semicolon (;), tab (\t for TSV), and pipe (|). The detector samples the first 2000 characters and picks the character with the highest occurrence count.
QDoes it handle quoted fields and multi-line values?
Yes — the parser is RFC 4180 compliant. It correctly handles fields wrapped in double quotes, escaped double-quotes (""), and cell values that contain newlines.
QHow do I export to Excel?
Switch to Table or CSV mode, then click the Excel export button (green spreadsheet icon). The xlsx library generates a proper .xlsx file with headers and all currently visible rows.
QIs my data sent to a server?
No. All parsing, conversion, and rendering happens locally in your browser. No data is transmitted to any server.