NorthSort / File check
Free file check
Drop a CSV or Excel file and see what is wrong with it: repeat rows, mixed date and phone formats, stray spaces, damaged accents and more. It runs in your browser. Your file never leaves your computer.
Drop a .csv or .xlsx file here
Files up to 15 MB. In an Excel file, the first visible sheet is checked.
Or paste a few rows instead
How you can tell it stays private
Load this page, switch off your internet, then drop your file. It still works, because nothing is sent anywhere.
The page also carries a security policy that blocks uploads and data connections, and loads nothing from other sites. There is no upload, no account and no cookie of ours.
What it looks for
- Repeat rows, and rows that share an email address
- Dates and phone numbers written in several different ways
- Dates that could be read day first or month first
- Numbers stored as text, and codes that lose their leading zeros
- Stray spaces, fillers such as N/A, and empty rows and columns
- Damaged accents, merged cells and hidden sheets
- Data we do not accept, such as full card numbers
What it cannot tell you
The file check counts problems. It does not fix the file, and it cannot judge what your data means: for example, which of two records is right, or whether 03/04/2026 is in March or April. Working that out with you is part of a paid job.
Want it fixed?
Send a sample of your file. You get a fixed price and a delivery date before any work starts.