Data converter

Tables and configuration files move between formats constantly and the conversion is usually trivial — which is exactly why it is not worth sending your data to a stranger to have it done. Everything here runs in your browser, so an export full of customer records or a config file with credentials in it never leaves your machine.

Up to 100 files at once. Mixed formats are fine.

Every data format we handle

10 formats in this category, 71 working conversions — 70 of them without your file leaving the device.

  • JSONJSON

    The data format of the web. Nested structures, read by every programming language.

  • NDJSONNDJSON

    One JSON object per line. What log pipelines and data exports stream.

  • CSVCSV

    A table as plain text. Every spreadsheet, database and analytics tool reads it.

  • TSVTSV

    Like CSV but tab separated, which avoids the comma-inside-a-field problem entirely.

  • ParquetParquet

    Columnar storage for large datasets. Far smaller and faster to query than CSV.

  • XMLXML

    The verbose ancestor of JSON. Still the backbone of enterprise and government data exchange.

  • YAMLYAML

    Indentation-based configuration format. Readable by people, picky about whitespace.

  • TOMLTOML

    A configuration format that stays readable without YAML’s indentation traps.

  • INIINI

    Sections and key-value pairs. The oldest configuration format still in daily use.

  • SQLSQL

    A table rewritten as INSERT statements, ready to load straight into a database.

Tools for data files

  • Somebody verifying that a download arrived intact and unmodified, usually comparing against a hash published on the project page they downloaded it from.

Where these conversions actually get interesting

CSV looks simple and is not. There is no single standard: separators differ by locale, quoting rules vary, and a field containing a comma or a newline is where most naive converters break. Numbers are the other trap — an identifier with leading zeros or a long number will be silently mangled by anything that guesses types too eagerly.

The structural mismatch matters more. JSON and YAML nest arbitrarily; CSV is flat. Converting a nested document to a table means deciding how to flatten it, and converting the other way means deciding what the columns become. There is no single right answer, which is why the pages say what they chose rather than pretending the question does not exist.

The bigger formats

Parquet is columnar and compressed, which makes it dramatically smaller and faster to query than the same data as CSV — often by an order of magnitude on anything large. It is the right format for data you will analyse repeatedly, and the wrong one for data a colleague needs to open in a spreadsheet.

Reading and writing it happens in your browser like everything else in this category, which for a dataset of any size is also simply faster than uploading it would be.

Data converter: common questions

Is my data uploaded anywhere?

No, and in this category that is often the whole reason to use it. Exports contain customer records, config files contain credentials, and neither should be pasted into a website. Everything here runs in your browser and nothing is transmitted.

Will long numbers and leading zeros survive?

That is the single most common way data conversion goes wrong, and it is why the pages state how types are handled rather than guessing eagerly. Where a value is ambiguous, preserving what you gave us is the priority.

How is nested JSON turned into a flat table?

By flattening, and the pages say how. There is no single correct answer to what a nested document should look like as columns, so the choice is stated rather than hidden.

Is there a row limit?

None that we impose. Because it runs locally the limit is your own memory rather than an upload cap, which for most files means there is effectively no limit at all.

Other things to convert