CSV Viewer Online
View and inspect CSV files directly in your browser. Browse rows, check column names and data types — no upload required, your data stays on your device.
About the CSV viewer
The CSV viewer opens a comma-separated file in the browser and shows what a program would see when it reads it, not just the raw text. It detects the delimiter, decides whether the first line is a header, and assigns a type to each column. You get the total row count, a schema table with each column's detected type, and the first 500 rows, 100 per page.
That makes it a quick check before importing a file into a database or sending it to someone. If a column you expect to be numeric is listed as VARCHAR, something in it is not a number. If there is only one column, the delimiter is probably a semicolon or tab that was not detected. Semicolon files are common from European versions of Excel, where the comma is the decimal separator. The file is read on your device and is not uploaded. Files up to 50 MB can be opened.
What to check when you open a CSV file
- The column count matches what you expect. A single wide column usually means the wrong delimiter.
- Headers look like names, not data. Names like column0 and column1 mean no header row was detected.
- Numeric columns show BIGINT or DOUBLE. VARCHAR means at least one value is text, such as N/A or 1,200.
- Date columns show DATE or TIMESTAMP rather than VARCHAR.
- Accented characters display correctly. Garbled text like é points to a file that is not UTF-8.
- The total row count matches the source system's export count.
Your file is processed locally in your browser and is never uploaded. The free limit is 50 MB per file; larger files work if your device has the memory for them.
Frequently Asked Questions
Why does the CSV viewer show only 500 rows?
The whole file is loaded and counted, and the row total at the top covers every row. Only the first 500 are displayed, 100 per page, to keep the page responsive. Use the SQL Query tool to look at rows further down or search the full file.
How are the column types decided?
They are inferred from the values. A column where every value is a whole number is BIGINT, decimals give DOUBLE, ISO dates give DATE, and anything mixed stays VARCHAR. CSV itself stores no types, so this is what most import tools would guess too.
What does an italic "null" in a cell mean?
The field was empty in the CSV. Empty fields are read as missing values rather than empty strings, which is also how databases usually import them.
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