Free contact CSV cleaner
Clean a contact spreadsheet before your next CRM import. Trim extra spaces, find duplicate rows and review records that share an email address, then download your cleaned CSV.
Free · No signup · Processed only in your browser
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How to clean a contact CSV file
- Export your contact sheet as a UTF-8 CSV with a unique name for every column in the first row.
- Choose your file or try the fictional sample. Auto-detect checks comma, semicolon and tab separators. If more than one fits, choose the separator used in your export and check the preview.
- Review the preview. Choose whether to trim surrounding whitespace and remove exact duplicate rows.
- Download all kept rows as a comma-separated CSV. Your original file is never modified.
Your contacts stay yours
File contents and the preview stay in this browser tab. This page does not load our website tracking or session-recording tag, and it does not save your list to browser storage or an account.
Rows with different details are never merged. Email conflicts are a prompt to review, not proof that two people are the same. This tool does not verify email delivery, normalize phone numbers, or establish permission to contact someone.
Remove duplicate rows without merging different contacts
An exact duplicate has the same value in every column after your chosen whitespace setting is applied. Enable duplicate removal to keep the first copy. Names with different letter casing, different phone numbers or different notes remain separate records.
For example, two identical rows for Maya can become one. Two rows for Alex that share an email address but have different phone numbers stay in the file and are flagged for review when you select the email column. A shared inbox does not necessarily mean the rows describe the same person.
Use this check for a sales contact list exported from a spreadsheet or another CRM. The cleaner helps prepare the file; it does not determine whether a record already exists in your destination CRM.
Contact CSV cleaner questions
Is this contact CSV cleaner free?
Yes. You can select a file, review changes and download the cleaned CSV without an account or payment. Processing happens in your browser; your contact file is not uploaded to NoClutterCRM.
Can I use an Excel or Google Sheets file?
Export the sheet as a UTF-8 CSV first. Workbooks, formulas, multiple sheets and formatting are not imported. Files can contain up to 5 MB, 10,000 data rows, 100 columns and 200,000 cells, with at most 10,000 characters per cell.
What gets changed?
Empty rows are removed; rows holding only spaces are removed while whitespace trimming is on. Whitespace trimming and exact-duplicate removal follow your selected options. Every column stays in its original position. Names, letter casing and phone formats remain as entered. By default every cell is exported exactly as cleaned, ready for a CRM import. If you will open the file in a spreadsheet, turn on Neutralise spreadsheet formulas: cells that start with = or with +, - or @ followed by a letter (=SUM(…), +SUM(…), @HYPERLINK(…)) get a leading apostrophe, and the download summary shows how many. Phone numbers such as +44 7700 900123 and amounts are never changed. When opening the CSV in a spreadsheet, import phone numbers and identifiers as text to preserve leading zeros.
Does downloading add these contacts to NoClutterCRM?
No. Download and review your cleaned file first. If you have a workspace, sign in and upload the file through Contacts → Import. The CRM has its own field mapping, permissions and import review. Nothing transfers from this tool automatically.
Give your clean list a next step.
Contact management in NoClutterCRM keeps contacts, conversations and follow-up tasks together. When you are ready, bring your reviewed CSV into your workspace.