# Using JSON format template variables
<a name="cloudwatch-using-json-format-template-variables"></a>

 Some queries accept filters in JSON format and Grafana supports the conversion of template variables to JSON. 

 If `env = 'production', 'staging'`, the following query will return ARNs of EC2 instances for which the `Environment` tag is `production` or `staging`. 

```
resource_arns(us-east-1, ec2:instance, {"Environment":${env:json}})
```