Website data is one of the items may occupy your storage unnecessarily. To delete and clear website data in Safari on iPhone and iPad devices (Specific website or the whole history), do as follows:
1. Open the Settings app
2. Scroll down to the list of default apps on your iOS running device and tap the Safari option to open its settings
3. Scroll all the way down to the Advanced settings and open it
4. Hit the Website Data option
5. Now, to Remove All Website Data from Safari on your iPad or iPhone, simply tap the "Remove All Website Data" button in the bottom, and confirm the removing process.
Tip: To remove data for a specific website, tap the Edit button on the top right followed by the Red minus button next to the website you want to delete the entire data. Finally tap the Delete button to confim it.