Free Online Data Converters
Convert data between formats without leaving the browser
Data rarely lives in the format you need it in. An API returns JSON but your pipeline expects CSV; a config file is YAML but the linter wants JSON; a sample response needs to become a TypeScript interface or a Go struct before you can use it in code. This category collects converters that translate between the formats developers touch every day — JSON, YAML, CSV, XML, TypeScript, Go, number bases, and text case conventions. Every converter is a pure client-side function: your data goes in, the converted output comes out, and nothing is sent anywhere.
All Data Converters
JSON → TypeScript
Convert JSON to TypeScript interfaces instantly. Generate strongly-typed TS types from any JSON sample.
JSON → Go
Convert JSON to Go structs online. Generates idiomatic Go structs with proper json tags and PascalCase field names.
JSON → Python
Convert JSON to Python @dataclass definitions with typed fields. snake_case field names, nested classes, List[T] for arrays, and JSON-key alias comments. 100% local.
JSON → PHP
Convert JSON to PHP 7.4+ classes with typed properties. Generates one class per nested object, phpdoc @var array<T> for typed arrays, and camelCase property names. 100% local.
JSON → Java
Convert JSON to Java POJOs with Jackson @JsonProperty annotations, camelCase field names, List<T> for arrays, and generated getters/setters. Optional package declaration. 100% local.
JSON → C#
Convert JSON to C# classes with System.Text.Json [JsonPropertyName] attributes, PascalCase properties, List<T> for arrays, and optional namespace. Works in .NET 6 / 7 / 8 / 9. 100% local.
JSON → Rust
Convert JSON to Rust structs with #[derive(Serialize, Deserialize)]. snake_case field names, #[serde(rename)] for mismatched keys, Vec<T> for arrays, and reserved-keyword raw identifiers. 100% local.
JSON → YAML
Convert JSON to YAML online. Preserve structure, comments-free, and ready to paste into Kubernetes or CI configs.
Data Size
Convert between bytes, KB, MB, GB, TB, PB and their IEC binary counterparts (KiB, MiB, GiB, TiB). Explains the SI vs IEC difference that causes 'my 1 TB drive shows 931 GB' confusion. 100% local.
Bandwidth
Convert between Mbps, MB/s, Gbps, Kbps and other network speed units. Includes a bit-vs-byte cheatsheet and estimated download times for common file sizes. 100% local.
Bitcoin Units
Convert between BTC, mBTC (milli-bitcoin), bit (μBTC) and satoshi denominations instantly. Uses BigInt math for full precision — no floating-point loss. 100% local, no live rates.
Ethereum Units
Convert between wei, gwei, ether and other Ethereum denominations with full BigInt precision. Perfect for gas price math, smart-contract arithmetic, and EVM debugging. 100% local, no live rates.
YAML → JSON
Convert YAML documents to JSON online. Supports YAML 1.2, multi-document streams, and produces pretty-printed JSON output.
JSON → CSV
Convert an array of JSON objects to CSV online. Headers are inferred automatically from all keys across records.
CSV → JSON
Convert CSV data to a JSON array of objects online. Auto-detects delimiter and quotes, preserves numeric types when requested.
Number Base
Convert numbers between binary, octal, decimal, and hexadecimal. Supports arbitrarily large integers using BigInt.
YAML Diff
Compare two YAML documents structurally by parsing both first. Ignores irrelevant format differences (quote style, comments, indentation) — you see only what actually changed. Handles multi-document YAML. 100% local.
XML Diff
Compare two XML documents structurally — elements, attributes, and text content. Ignores comments, whitespace, and attribute order. Uses the same path convention as our XML → JSON converter (@attr, #text). 100% local.
JSON5 → JSON
Convert JSON5 or JSONC to strict RFC 8259 JSON online. Strips // and /* */ comments, single quotes, unquoted keys, trailing commas, hex numbers, and NaN / Infinity. 100% local.
XML → JSON
Convert XML to JSON online. Handles attributes, CDATA, nested elements, and repeated siblings. Compatible with fast-xml-parser / xml2js output conventions. 100% local.
JSON → XML
Convert JSON to XML online. Attributes via @-prefixed keys, #text for element content, automatic array-to-repeated-siblings expansion. Emits a valid XML declaration. 100% local.
CSV to SQL INSERT
Convert CSV data to SQL INSERT statements. Configurable table name, auto-detects column headers from the first row, handles NULL, numbers, quotes, and string escaping. 100% local.
TOML to JSON
Convert TOML configuration files to JSON. Handles key-value pairs, table sections, arrays, numbers, strings, and booleans. Common in Rust, Python, and Go projects (Cargo.toml, pyproject.toml). 100% local.
HTML to Markdown
Convert HTML to clean Markdown. Handles headings (h1-h3), bold, italic, links, images, lists, and code. Strips complex HTML tags and formatting. 100% local.
Morse Code
Convert text to Morse code and decode Morse back to text. Supports letters A-Z, digits 0-9, and punctuation. Real-time conversion with audio-style visual representation. 100% local.
Number to Words
Convert numbers to English words. Supports integers up to trillions. For checks, legal documents, and education. 100% local.
SQL to CSV
Convert SQL INSERT statements back to CSV. Extracts column names and values. Reverse of CSV to SQL INSERT. 100% local.
YAML Validator
Validate YAML syntax online. Paste your YAML and get instant pass/fail with the exact error location — line number and column. 100% local.
Markdown Preview
Live Markdown preview — type on the left, see rendered HTML on the right. Supports GFM tables, fenced code blocks, task lists, and strikethrough. 100% local.
Color Picker
Pick any color and instantly get its HEX, RGB, and HSL values. Click to copy any format. Use the native color wheel or type a HEX code. 100% local.
When to use these tools
Use these tools when you need to move data between systems that speak different formats, generate typed code from a sample payload, or normalize identifiers between programming-language naming conventions.
Frequently Asked Questions
Are the conversions lossless?
For structurally compatible formats (JSON ↔ YAML) the conversion is lossless. For formats with different capabilities (JSON ↔ CSV), some information — like nested structures — is serialized as strings or flattened; each tool page explains the trade-offs.
How large a document can I convert?
There is no hard limit. In practice, browsers handle a few megabytes smoothly. For very large exports, stream-process the file server-side rather than in the browser.