>_QueryLocalCSV & JSON tools that run in your browser
QueryLocal / CSV viewer

Online CSV viewer

See what's inside a CSV in seconds — no Excel, no upload, no install.

What you see when you drop a file

  • The exact row and column count — useful to check an export is complete before you send it on.
  • The detected separator (comma, semicolon, tab, pipe) and the column names, cleaned up so they can be used in queries.
  • The first 1,000 rows, paged 50 at a time. Change the query to look anywhere else in the file.

Find something specific

Scrolling through a million rows isn't viewing, it's hoping. Ask for what you're looking for instead:

SELECT *
FROM data
WHERE email LIKE '%@example.com'
LIMIT 100;

Or click Column summary to see, for every column, how many cells are filled, how many distinct values it has and its minimum and maximum — the quickest way to spot empty columns, broken dates or outliers.

Why not just use a text editor?

A text editor shows raw lines: quoted fields containing commas or line breaks break the visual alignment, and big files make it crawl. QueryLocal parses the CSV properly (quoted fields, escaped quotes, Windows and Mac line endings, UTF-8 byte-order marks) and shows a real table.

Other free CSV tools

Open a CSV too big for ExcelMillions of rows, hundreds of MB. No 1,048,576-row limit. Remove duplicate rowsDeduplicate a CSV in one click, then download it clean. CSV to JSONConvert a CSV into a JSON array of objects, typed numbers included. JSON to CSVFlatten a JSON array or JSON Lines file into a clean CSV. Semicolon ⇄ comma CSVFix Excel's semicolon CSVs, or make one Excel will open. Count rows in a CSVExact row count of any CSV, even a huge one, in seconds. Filter a CSVKeep only the rows you need and download them. Column summaryFilled, distinct, min and max for every column at once. Query CSV with SQLReal SQLite on your file: GROUP BY, JOINs, window functions.

Frequently asked questions

Which file types can I open?

CSV, TSV and other delimited text files (.csv, .tsv, .txt), plus JSON arrays and JSON Lines (.json, .jsonl, .ndjson).

Is my file uploaded?

No. Your browser reads the file locally and the analysis runs in the page itself. There is no server-side component.

Can I edit cells?

The viewer is read-only on your original file, but you can transform the data with a query (rename, compute, filter) and download the result as a new file.