# Sigmera

> Client-side data cleaning tools for CSV and spreadsheets. Remove duplicates, clean phone numbers and emails, and split names — 100% in your browser, GDPR-safe, nothing uploaded to a server.

Sigmera is a client-side, no-upload, GDPR-safe data-cleaning toolkit for CSV and spreadsheet files, built for non-technical users. All processing happens in the browser; files are never uploaded to a server. Free to try; a free account unlocks downloads and the pipeline workspace.

## Tools
- [Remove duplicates from CSV](https://www.sigmera.app/tools/remove-duplicates-csv): Delete duplicate rows by any column, keep the first or last match, and download a clean file.
- [Clean phone numbers](https://www.sigmera.app/tools/clean-phone-numbers): Format a messy column of phone numbers to the E.164 standard, with no upload.
- [Clean email column](https://www.sigmera.app/tools/clean-email-column): Lowercase, trim, validate, and dedupe an email column in a CSV — entirely in your browser.
- [Split full names](https://www.sigmera.app/tools/split-full-names): Break a full-name column into separate first and last name fields, with optional middle name.
- [Combine columns](https://www.sigmera.app/tools/join-columns-csv): Merge two or more CSV columns into one — pick a separator and name the new field.
- [Find and replace in a CSV](https://www.sigmera.app/tools/find-and-replace-csv): Swap text in a column like Excel's Find & Replace — match case or whole cell, with no upload.
- [Convert CSV to Excel](https://www.sigmera.app/tools/convert-csv-to-excel): Turn a CSV into a formatted .xlsx workbook in your browser — no upload, no install.
- [Convert Excel to CSV](https://www.sigmera.app/tools/convert-excel-to-csv): Export the first sheet of an .xlsx or .xls file to a clean CSV — entirely in your browser.
- [Visualize a CSV as a chart](https://www.sigmera.app/tools/visualize-csv): Summarize a spreadsheet into a bar, line, area or pie chart and export the image — nothing uploaded.

## Guides
- [How to remove duplicates in Excel](https://www.sigmera.app/guides/remove-duplicates-in-excel): Find and delete duplicate rows with the Remove Duplicates button, COUNTIF, or Google Sheets.
- [How to split full names in Excel](https://www.sigmera.app/guides/split-full-names-in-excel): Separate a full-name column into first and last name with Text to Columns or formulas.
- [How to format phone numbers in Excel](https://www.sigmera.app/guides/normalize-phone-numbers-csv): Standardize a messy phone column to a consistent format, including the E.164 standard.

## Use cases
- [Clean a CSV before a HubSpot import](https://www.sigmera.app/use-cases/clean-csv-before-hubspot-import): Fix phone numbers, normalize emails, and remove duplicates so your HubSpot import succeeds the first time.
- [Deduplicate sales leads](https://www.sigmera.app/use-cases/deduplicate-sales-leads): Strip duplicate leads out of an export so your pipeline numbers and outreach don't double-count people.
- [Clean recruitment data](https://www.sigmera.app/use-cases/clean-recruitment-data): Dedupe an applicant list and split candidate full names into first and last name fields for your ATS.
- [Clean a customer list before a CRM import](https://www.sigmera.app/use-cases/clean-customer-list-before-crm-import): Validate and dedupe an email column so your CRM doesn't reject rows or create duplicate contacts.

## Comparisons
- [CSV cleaner without upload, compared](https://www.sigmera.app/compare/csv-cleaner-without-upload): In-browser vs server-based vs desktop vs Excel — compared on privacy, GDPR safety, install, and row limits.
- [Sigmera vs OpenRefine](https://www.sigmera.app/compare/sigmera-vs-openrefine): A fair OpenRefine alternative comparison — a powerful desktop tool vs a simple, no-install browser tool.

## Blog
- [How to clean a CSV before a CRM import](https://www.sigmera.app/blog/clean-a-csv-before-a-crm-import): Clean a CSV before a CRM import the right way — remove duplicates, fix phone numbers and emails, and match name fields, all in your browser.

## Alternatives
- [Best OpenRefine alternatives](https://www.sigmera.app/alternatives/openrefine): The best OpenRefine alternatives in 2026, compared on power, learning curve, privacy, and whether you must upload your data — and who each one is really for.

## Import guides
- [Clean CSVs for HubSpot](https://www.sigmera.app/integrations/hubspot): Clean a CSV before a HubSpot import in your browser — remove duplicates, fix phones and emails, and split names so every row imports. Nothing uploaded.

## More
- [Pricing](https://www.sigmera.app/pricing)
- [Pricing (markdown)](https://www.sigmera.app/pricing.md)
- [Privacy](https://www.sigmera.app/privacy)
- [Terms](https://www.sigmera.app/terms)