Profile every CSV column before you clean it.
Measure completeness, uniqueness and repetition in your browser before applying a transformation. The profile updates with the preview so you can see what each cleaning step actually changes.
1. Choose a CSV to profile
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
- Inspect missing, unique and repeated values
- Choose any cleanup rules, review and download a new CSV
Find missing and repeated values
Each column shows filled and empty counts, unique values, duplicate values, and value lengths. These measures help locate weak identifiers, incomplete fields and unexpectedly repeated categories.
Compare the original with the preview
Profiles recalculate against the current cleaning plan. A shift in uniqueness or empty values becomes visible before you export, which makes unintended changes easier to catch.
Inspect locally by default
Browser-local profiling does not send the CSV to Loam or Claude. Accepted files can contain up to 100,000 rows, 500 columns and 20 MiB of data.
Move to governed work when needed
Local profiling is useful for a bounded file. For durable, permissioned work on shared data, open Loam and create a source-preserving view under the existing workspace controls.
Frequently asked questions
What does the CSV column profile measure?
The profile shows filled, empty, unique and repeated values plus value lengths for each column. It updates with the cleaning preview so you can compare the effect of your rules.
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.