Use automation to find problems, not to hide decisions.
Good data cleaning separates predictable transformations from ambiguous identity decisions. This tool applies explicit rules and surfaces likely matches for review instead of presenting uncertain guesses as facts.
1. Choose a CSV to clean
Your file opens directly in the local app. Contents stay in this browser; no account needed.
Up to 20 MiB, 100,000 rows and 500 columns.
- Choose CSV
- Profile and choose cleanup rules
- Review and download a new CSV
Automate deterministic cleanup
Whitespace, text case, empty-value conversion and exact deduplication follow rules you select. The same source and ordered plan produce the same preview, which makes the result explainable.
Keep identity decisions human
A high similarity score does not prove that two people or companies are the same. Fuzzy matching identifies candidates, shows the evidence, and leaves the records untouched.
See what changed before export
The plan, row preview and updated column profiles provide a review trail. You can undo the latest step or reset everything without modifying the original CSV.
Use Claude only with governed Loam data
For durable workspace data, the dedicated Data Cleaning MCP surface uses ordinary Loam permissions and seven focused cleaning tools. It does not receive browser-local files or proxy arbitrary data APIs. Connecting requires Login with Loam, an eligible workspace account, and explicit consent for the requested capability.
Frequently asked questions
Does AI decide which records to delete?
No. The local tool applies deterministic rules you select. Similarity scores suggest possible matches for human review and never delete records automatically.
Can Claude clean the CSV I open in this browser?
Browser-local files do not enter MCP. The separate Data Cleaning MCP connection works with governed Loam data after sign-in, workspace selection and explicit consent.
Is my CSV uploaded when I clean it locally?
No. Local cleaning processes the CSV in this browser without an account. Temporary Loam mode is a separate option and uploads a copy only after you confirm it in the application.
Which files can I clean?
Local mode accepts one CSV up to 20 MiB, 100,000 rows and 500 columns. Export other formats as CSV first. Download your cleaned result before refreshing or closing the tab.
Does cleaning overwrite my original CSV?
No. Rules change a preview that you can undo or reset. Export downloads a separate cleaned CSV and processes the complete accepted file.