CSV guide

How to open a large CSV in your browser

Unwrap lets you inspect a large file before you decide whether you need to load every row.

Open a CSV Your file stays in your browser.

What happens when you open a large CSV

Unwrap initially loads up to one million rows. You can browse those rows, review the columns, and check the file settings.

If the CSV is larger, Unwrap marks the results as a sample. Select Load full file when you want the column results to include every row.

How it works

Scroll through large tables

Large tables remain easy to browse. You can move through the rows, compare values, and keep the column names in view as you scroll.

When should you load the full file?

Load every row when you need complete counts, missing-value rates, or other column results. The sample is enough if you only want to check that the CSV opens correctly, see its columns, or read a few records.

Loading the full file may take longer and use more memory. How much depends on the file and your device.

If the full file is too large

Loading every row takes more browser memory than checking a sample. If the full load fails, you can still use the sample to inspect the columns and a few records. For complete results, try a device with more available memory or split the CSV with a CSV-aware tool.

Common questions

How large can the CSV be?

There is no fixed file-size limit. What works depends on the available memory in your browser, especially when you load every row.

Should I split the CSV first?

Usually not. Try opening it in Unwrap first. If your browser runs out of memory, a CSV-aware splitting tool may help. Avoid splitting the file as plain text because quoted values can contain line breaks.

Continue exploring

• CSV viewer — learn what the different views show
• CSV column analyzer — take a closer look at individual columns
• CSV vs Excel — choose the right tool for the next step