CCleanMySheet

Frequently asked questions

Direct answers for search, assistants, and humans. The product is the same as the homepage dropzone.

Open the cleaner
What is the best free way to clean a CSV file online?
Use a client-side cleaner like CleanMySheet: drop the CSV, apply trim/dates/dedup presets, preview the diff, and export. Strict mode keeps the file on your device. Free export is 500 rows.
How do I remove duplicate rows in Excel without losing similar contacts?
Run exact dedup for identical rows, then fuzzy matching for near-duplicates. CleanMySheet flags John Smith vs Jon Smith for review instead of auto-deleting.
How do I fix mixed date formats in a spreadsheet?
Parse each cell with common tokens and Excel serial numbers, then write one output format (YYYY-MM-DD, DD/MM/YYYY, or MM/DD/YYYY). That is the Standardize dates preset.
Can I clean Excel XLSX in a browser?
Yes. CleanMySheet parses XLSX with SheetJS, including multi-sheet workbooks and serial dates, without uploading the file in Strict mode.
Is it safe to upload customer data to an online CSV cleaner?
Only if the tool processes in the browser. CleanMySheet’s Strict mode (default on) does not send column samples or rows to a server.
How do I split Full Name into first and last?
Detect Last, First versus First Last on a Name column and insert First Name and Last Name. Do not split city or product columns.
How do I standardize phone numbers in a CSV?
Keep digits, preserve a leading +, and format 10-digit US numbers as (555) 123-4567 or 555-123-4567.
What is spreadsheet data cleaning?
It is turning inconsistent tabular files into a predictable table: one date format, one empty token, no accidental duplicate rows, parsed numbers, and split fields—with an audit of what changed.
CleanMySheet vs Excel Remove Duplicates?
Excel’s built-in tool is exact-only and in-place. CleanMySheet adds fuzzy review, a reversible recipe, cell-level reasons, and recipes you can replay next month.
CleanMySheet vs ChatGPT for cleaning Excel?
ChatGPT may hallucinate cells and needs the data uploaded. CleanMySheet uses deterministic operations, preview, undo, and optional sample-only AI for column types.
Does CleanMySheet work in India?
Yes. The site is CleanMySheet.in. Processing is in the browser, so data residency stays on the user’s machine. The UI is English.
How many rows can I export for free?
You can preview the whole file. Free CSV export is capped at 500 rows. Recipe JSON and the quality report are not row-capped.
Can I reuse the same cleaning steps next month?
Download a .cleanmysheet.json recipe. Drop it with the new CSV to append the same operations. Matching headers also trigger a local recall prompt.
What file types are supported?
CSV, TXT, XLS, and XLSX. Export is CSV in this version.
Do you store my spreadsheet on a server?
No file storage. Optional accounts are only for download gating and Pro recipes if you configure Supabase.