Free Data Tools

Small, fast tools for everyday data work: converting files, checking JSON, generating SQL and calculating statistics.

All tools are free, need no sign-up and run entirely in your browser, so your data is never uploaded.

Convert and clean data

• CSV to JSON converter

  Convert CSV to JSON or JSON to CSV, with type detection, nested-object flattening and a preview table.

• Excel to CSV converter

  Turn any sheet of an .xlsx, .xls or .ods workbook into CSV or JSON. Export one sheet or all of them.

• JSON formatter and validator

  Format, minify and validate JSON, with the exact line and column of any error and hints for common mistakes.

• CSV to SQL converter

  Generate CREATE TABLE and INSERT statements for PostgreSQL, MySQL, SQLite or SQL Server, with column types detected.

• Unix timestamp converter

  Convert epoch timestamps to dates and back, in seconds, milliseconds, microseconds or nanoseconds.

Statistics and machine learning

• Descriptive statistics calculator

  Mean, median, standard deviation, quartiles, skewness, a confidence interval, outliers, a histogram and a box plot.

• Correlation coefficient calculator

  Pearson and Spearman correlation, R², p-values and a scatter plot with a regression line.

• Confusion matrix calculator

  Accuracy, precision, recall, F1, specificity and MCC from four counts or a list of labels.

Learn to do it yourself

Each tool page shows the Python, pandas or SQL code that does the same job, so you can automate it. For the full skills behind them, start with these tutorials:

• Data manipulation with pandas
• SQL for data analysis
• Exploratory data analysis in Python
• How to analyze data in Excel

Missing a tool you’d use? Tell us.