# API Gateway API key file format
<a name="api-key-file-format"></a>

API Gateway can import API keys from external files of a comma-separated value (CSV) format, and then associate the imported keys with one or more usage plans. The imported file must contain the `Name` and `Key` columns. The column header names aren't case sensitive, and columns can be in any order, as shown in the following example: 

```
Key,name
apikey1234abcdefghij0123456789,MyFirstApiKey
```

A `Key` value must be between 20 and 128 characters. A `Name` value cannot exceed 1024 characters. 

An API key file can also have the `Description`, `Enabled`, or `UsagePlanIds` column, as shown in the following example: 

```
Name,key,description,Enabled,usageplanIds
MyFirstApiKey,apikey1234abcdefghij0123456789,An imported key,TRUE,c7y23b
```

When a key is associated with more than one usage plan, the `UsagePlanIds` value is a comma-separated string of the usage plan IDs, enclosed with a pair of double or single quotes, as shown in the following example:

```
Enabled,Name,key,UsageplanIds
true,MyFirstApiKey,apikey1234abcdefghij0123456789,"c7y23b,glvrsr"
```

Unrecognized columns are permitted, but are ignored. The default value is an empty string or a `true` Boolean value. 

The same API key can be imported multiple times, with the most recent version overwriting the previous one. Two API keys are identical if they have the same `key` value. 

**Note**  
For best practices to consider, see [Best practices for API keys and usage plans](api-gateway-api-usage-plans.md#apigateway-usage-plans-best-practices).