Field notes
Practical answers for unwieldy data files.
How to open, inspect, filter and troubleshoot CSV and JSON Lines files without handing your data to a website.
How to open an 8 GB CSV
Choose a file-backed viewer and verify every row arrived.
CSV too large for Excel
Understand the grid limit and preserve the full dataset.
Inspect a large JSONL file
Turn newline-delimited objects into useful columns.
Open CSV without uploading
A practical privacy checklist for offline viewers.
Filter a 5 GB CSV with regex
Stack text, number and date filters safely.
UTF-8 and weird-looking CSVs
Why accents, symbols and columns go wrong in Excel.
CSV analytics without a database
Profile and pivot huge files locally.