# Generating checksums for a file

An MD5 checksum is a 32-character hexadecimal number that's computed on files. A SHA-256 checksum is an equivalent 64-character hexadecimal number. These values can be used to verify data integrity against unintentional file corruption during transfer.

**Generating MD5 Checksum**

**Windows**

1. Open **Command Prompt** - Press Windows + R, type cmd and press enter.
2. Navigate to the folder that has the file for which the integrity needs to be verified: type `cd` followed by the path to the folder having the file to do so.

Tip: Open the folder having the file in Windows Explorer, then drag and drop it in Command Prompt to inset the path.

3. Type the following command.

```
certutil -hashfile <File whose MD5 needs to be computed> MD5  
```

```
certutil -hashfile <File whose SHA256 needs to be computed> SHA256  
```

For example, in order to generate the MD5 checksum for a Oracle Linux 8 ISO file:

![](https://761066130-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FGM9W2DuBTgEXv1ClCm8H%2Fuploads%2Fgit-blob-c2855fdf62fd5c4c7a5e388ad958d6ddfb445c30%2Fimage1.png?alt=media\&token=6fc50506-47c0-473b-bfcb-8ff0c3b068db)

**Linux**

1. Open **Terminal**
2. Navigate to the folder that has the file for which the integrity needs to be verified: type `cd` followed by the path to the folder having the file to do so.
3. Run the following command.

```
md5sum <File whose MD5 needs to be computed>  
```

```
sha256sum <File whose SHA256 needs to be computed>  
```

For example, in order to generate the MD5 checksum for a Oracle Linux 8 ISO file:

![](https://761066130-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FGM9W2DuBTgEXv1ClCm8H%2Fuploads%2Fgit-blob-5e9a32acc880bf9c50a28cba20ea1574d23690a8%2Fimage2.png?alt=media\&token=8c30d12b-3a1e-428c-9625-e70956a6e501)

Verify if the **estimated MD5/SHA-256** **matches** the **MD5/SHA-256 value provided by the file's original owner**. If the two checksums are different, the **file is likely corrupted**. Re-transfer the file and repeat the process.

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