How to Diagnose CSV File Errors Before Importing
Find malformed rows, duplicate headers, wrong delimiters, BOMs, mixed line endings, and type problems before a CSV reaches Excel, a CRM, or a database.
When a CSV import fails, the problem is often structural rather than missing data. One row may contain a different number of fields, a header may be empty, or the file may use semicolons instead of commas.
HappyCSV's CSV Diagnostic reports the likely delimiter, line endings, row and column counts, duplicate headers, empty headers, parser errors, and simple type signals without changing the original file.
What to check
- Confirm the delimiter: comma, tab, semicolon, or pipe.
- Confirm that every data row has the same number of fields as the header.
- Look for duplicate or empty header names.
- Check for a UTF-8 BOM and mixed line endings.
- Check that dates, numbers, and identifiers are not mixed unintentionally.
Run the diagnostic first, then use Repair Broken CSV, Fix Encoding, or Remove Empty Rows for the specific problem. This review-first workflow is safer than automatically rewriting a file you have not inspected.
Related Articles
Convert CSV Latitude and Longitude to GeoJSON
Convert latitude and longitude columns into GeoJSON point features for maps, GIS software, and location-data workflows.
Convert CSV to ICS Calendar Events
Convert rows with dates and event details into an ICS file for Google Calendar, Outlook, Apple Calendar, and iPhone.
Convert CSV to NDJSON JSON Lines
Convert every CSV row into newline-delimited JSON for APIs, logs, BigQuery, and data pipelines.
Need to handle CSV files?
HappyCSV is the free, secure way to merge, split, and clean your data — all in your browser.