# What is a CSV file?

> CSV (comma-separated values) is a plain text format for table data that almost every business tool can export and import. Its quirks and how n8n reads it.

Source: https://learn.ynteractive.com/content/glossary/csv · Updated 2026-10-01 · Free from Stepthrough (https://learn.ynteractive.com)

[Data, Sheets and Gmail](https://learn.ynteractive.com/content/glossary#topic-data-sheets-and-gmail) · [AI glossary](https://learn.ynteractive.com/content/glossary)

Updated October 1, 2026 · By [Robert Breen](https://learn.ynteractive.com/content/about)

CSV (comma-separated values) is a plain text file format for table data: each line is a row and commas separate the columns, usually with a header line first. Almost every spreadsheet, CRM and accounting tool can export and import it.

## Why it matters for a small business

CSV is the common language of business data. When two tools have no direct connection, you can almost always download a CSV from one and upload it to the other: a customer list from booking software into an email tool, a bank export into a bookkeeping sheet, a month of leads for your accountant.

Its simplicity is also its weakness. There are no data types, formulas or formatting, so leading zeros in ZIP codes can vanish and dates can flip between US and international order when the file is opened. A comma inside a value (like "Smith, Jane") has to be wrapped in quotes, or every column after it shifts.

## In a real lesson: Daily Job Alerts: Email Each Tech Their Jobs from Google Sheets with n8n

No Stepthrough lesson works with a CSV file directly. The closest is the [Daily Job Alerts lesson](https://learn.ynteractive.com/content/n8n-daily-job-alerts-google-sheets-gmail), because it shows the shape table data takes once n8n reads it. The Jobs tab for Rapid Flow Plumbing (a made-up company) has a header row (Customer, Address, Job, Time, Tech, Tech Email) and one row per job. **Get row(s) in sheet** turns those six rows into six items, each labeled with the column names.

A CSV of the same jobs would hold the identical table as text: a header line, then one line per job. In n8n, the **Extract from File** node can read a CSV into items like those, and **Convert to File** can write items back out as CSV. After that, the lesson's Filter and Gmail steps would work exactly the same way.

[Try this lesson free](https://learn.ynteractive.com/modules/job-alerts) or [read the step-by-step guide](https://learn.ynteractive.com/content/n8n-daily-job-alerts-google-sheets-gmail).

## Common confusions

### CSV vs Google Sheets

A [Google Sheet](https://learn.ynteractive.com/content/glossary/google-sheets) is a live document that people and workflows can read and edit. A CSV is a static snapshot; exporting one freezes the data at that moment.

### CSV vs JSON

CSV is flat: rows and columns. [JSON](https://learn.ynteractive.com/content/glossary/json) can nest data, like an order with a list of items inside it. n8n works in JSON internally and turns each CSV row into a JSON item.

### CSV vs Excel (.xlsx)

An .xlsx file can hold several sheets, formulas and formatting. A CSV holds one table of plain values.

## Tips

- Use your spreadsheet's import option, not a double-click, when date and number formats matter.
- Keep a header row; most tools match columns by those names.
- Before uploading a CSV to an AI tool, delete columns of personal data you don't need.

## Related terms

[Google Sheets (as an automation database)](https://learn.ynteractive.com/content/glossary/google-sheets) · [JSON](https://learn.ynteractive.com/content/glossary/json) · [Field mapping](https://learn.ynteractive.com/content/glossary/field-mapping) · [Item (n8n)](https://learn.ynteractive.com/content/glossary/item) · [Personally identifiable information (PII)](https://learn.ynteractive.com/content/glossary/pii)

## Where to learn more

[n8n tutorials](https://learn.ynteractive.com/content/tool/n8n) · [Business Automations](https://learn.ynteractive.com/content/course/business-automations)

## Prompt templates that use it

[Sales pipeline review prompt](https://learn.ynteractive.com/content/prompts/sales-pipeline-review-prompt)

## Frequently asked questions

**How do I export a Google Sheet as a CSV?**

In Google Sheets, choose File, then Download, then Comma-separated values. It downloads the current tab only.

**Can n8n read a CSV file?**

Yes. The Extract from File node reads a CSV, and each row becomes an item with the header names as field names.

**Why do my ZIP codes lose their leading zero?**

The spreadsheet treated them as numbers when it opened the CSV. Import that column as text instead.

[All AI glossary terms, A to Z](https://learn.ynteractive.com/content/glossary) · [Free prompt templates](https://learn.ynteractive.com/content/prompts)