---
title: Supported File Formats
description: File formats supported for data import in Twenty.
---

## Supported Formats

Twenty supports three file formats for import:

| Format             | Extension | Notes                        |
| ------------------ | --------- | ---------------------------- |
| **CSV**            | .csv      | Recommended, most compatible |
| **Excel**          | .xlsx     | Modern Excel format          |
| **Excel (Legacy)** | .xls      | Older Excel format           |

## File Requirements

| Requirement      | Value                                 |
| ---------------- | ------------------------------------- |
| **Encoding**     | UTF-8 recommended                     |
| **Record limit** | 10,000 records per file               |
| **Structure**    | First row must contain column headers |
| **Content**      | One object type per file              |

## CSV Best Practices

* **Delimiter**: Use comma (`,`) or semicolon (`;`)
* **Text qualifier**: Use double quotes (`"`) for text containing commas
* **Line endings**: Windows (CRLF) or Unix (LF) both supported
* **Empty values**: Leave cells empty, don't use "NULL" or "N/A"

## Excel Best Practices

When exporting from Excel:

* Remove formulas (export values only)
* Delete empty rows at the end
* Ensure no merged cells
* Use the first sheet only

## Large Datasets

For datasets larger than 10,000 records:

* Split into multiple files
* Or use the [API import](/l/ko/user-guide/data-migration/how-tos/import-data-via-api) for unlimited records

<Note>For very large migrations (100,000+ records), the API is significantly faster and more reliable than CSV imports.</Note>