Question 1

What is a CSV file?

Accepted Answer

A CSV file is a plain text file used to store tabular data in rows and columns, with values separated by commas. CSV stands for Comma-Separated Values. It's one of the simplest and most widely supported data formats in the world.

Question 2

How do I open a CSV file?

Accepted Answer

You can open a CSV file using a CSV viewer like OpenCSV, a spreadsheet app such as Excel or Numbers, a database tool, or any plain text editor. OpenCSV opens CSV files instantly in your browser without installing anything.

Question 3

Why are CSV files important?

Accepted Answer

CSV files are universally compatible and used to import, export, and transfer structured data between systems. They power business operations, ecommerce, analytics, AI workflows, and almost every software integration that moves data between platforms.

Question 4

Can I edit CSV files?

Accepted Answer

Yes. CSV files can be edited using any CSV editor, spreadsheet app, or text editor. OpenCSV lets you click any cell to edit it, add or remove rows and columns, search inside the file, and save changes — directly in your browser, on any device.

Question 5

How big a CSV file can OpenCSV open?

Accepted Answer

OpenCSV comfortably handles files with hundreds of thousands of rows in modern browsers. The exact limit depends on your device's memory, but most real-world CSV exports — customer lists, inventory, analytics — open in seconds.

Question 6

Is there a file size limit when saving to the cloud?

Accepted Answer

Yes. Each cloud-saved file is capped at 5 MB so the app stays fast on every device. There's no limit on opening, editing, or downloading files locally — only on cloud sync. Files over 5 MB can still be opened and edited in the browser, then downloaded directly to your device.

Question 7

Does OpenCSV support tab-separated (TSV) or pipe-delimited files?

Accepted Answer

OpenCSV auto-detects the most common delimiters when you open a file. The default is comma. We're adding explicit delimiter selection in a future Pro tier for tab, semicolon, and pipe.

You want to…	Use
Quickly look at the data	OpenCSV
Edit a few cells, save back	OpenCSV
Run formulas, build a pivot table	Excel / Sheets
Inspect a corrupt or unusual file	Text editor
Open a really big file (100k+ rows)	OpenCSV
Open on a phone with no apps installed	OpenCSV

How to open a CSV file

Option 1 — Open in a CSV viewer (recommended)

Steps

Option 2 — Open in a spreadsheet app

Excel (Windows / Mac)

Numbers (Mac / iOS)

Google Sheets

Option 3 — Open in a text editor

When to use it

Which one should you use?

Frequently Asked Questions

Related guides

Open, edit, and share CSVs in seconds.