# How to convert .Pem to .Crt and .Key

To convert a `.pem` file into separate `.crt` (certificate) and `.key` (private key) files, you can use the `openssl` command-line tool. Here's how to do it:

### Step 1: Understand the `.pem` File

A `.pem` file may contain several elements, such as:

- The private key.
- The public certificate.
- The certificate chain (optional).

Typically, the private key and public certificate are stored in the `.pem` file.

### Step 2: Extract the Private Key

To extract the private key from the `.pem` file:

```bash
openssl pkey -in yourfile.pem -out private.key
```

- `in yourfile.pem`: The input `.pem` file.
- `out private.key`: The output file for the private key.

### Step 3: Extract the Certificate

To extract the certificate from the `.pem` file:

```bash
openssl x509 -in yourfile.pem -out certificate.crt
```

- `in yourfile.pem`: The input `.pem` file.
- `out certificate.crt`: The output file for the certificate.

### Summary of Commands

- **Extract private key**:
    
    ```bash
    openssl pkey -in yourfile.pem -out private.key
    ```
    
- **Extract certificate**:
    
    ```bash
    openssl x509 -in yourfile.pem -out certificate.crt
    ```
    

### Example

If your `.pem` file is named `combined.pem`, you can use the following commands:

1. **Extract the private key**:
    
    ```bash
    openssl pkey -in combined.pem -out private.key
    ```
    
2. **Extract the certificate**:
    
    ```bash
    openssl x509 -in combined.pem -out certificate.crt
    ```
    

### Explanation

- **private.key**: This file contains the private key extracted from the `.pem` file.
- **certificate.crt**: This file contains the public certificate extracted from the `.pem` file.

Now, you have your private key in `private.key` and your certificate in `certificate.crt`. These files can be used as needed, for instance, in web server configurations or other services requiring separate certificate and key files.