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CSV & Data Tools

Process, validate, and transform CSV datasets with free tools that never upload your data or add watermarks.

Every tool is free, watermark-free, and runs entirely in your browser—nothing uploads to our servers. If anything needs extra permissions, we call it out right away.

CSV Validator

Check CSV structure, delimiters, and header consistency with instant validation feedback.

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CSV Column Picker

Select and export specific columns from large CSV files in seconds.

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CSV Deduplicator

Remove duplicate rows using any column as a unique key.

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CSV Merge & Join

Join two CSV datasets on matching columns with a left-join workflow.

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CSV to HTML Table

Convert CSV data into responsive HTML table markup for websites and dashboards.

Visit CSV to HTML Table

CSV to Markdown Table

Create GitHub-ready markdown tables from CSV files instantly.

Visit CSV to Markdown Table

CSV Pivot Table Builder

Summarise CSV data with drag-free pivot table generation and export.

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CSV to NDJSON

Transform CSV rows into newline-delimited JSON for streaming pipelines.

Visit CSV to NDJSON

CSV Sorter

Sort massive CSV files by one or multiple columns without uploading data.

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CSV Statistics Explorer

Calculate column averages, mins, maxes, and percentiles entirely in your browser.

Visit CSV Statistics Explorer
offlinewebtools.com

312 free calculators, converters, and creative helpers that stay on your device—nothing uploads to our servers. Every tool is watermark-free, runs entirely in your browser, and never uploads to our servers or asks for an account.

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