A question we get asked often when people are asking for some more information on car rental with us is: "Do I need an international driving license for Thailand?" There are a few things we can say about this.

Let us start with the actual document. It is called an "International Driving Permit" and not an "International Driving License". In fact there is no such thing as an international driving license. 
If you do a search online there are websites that offer an international driving license for Thailand. We also see these advertised locally here. In our opinion these are mostly scams or at least invalid/unacceptable documents. The only document that is considered legal and valid is the International Driving Permit, or IDP, issued by local affiliated clubs, which are appointed by the FIA and IAT in cooperation with the local governments. The validity of the document is usually for 1 year. Inside the booklet there is a photo of the person it is issued to, the classes of the permitted vehicles this person is allowed to drive, and an array of translations that explain that the holder is considered to be able to operate these vehicles under the international agreements.
A very important fact that is often forgotten is that the international driving permit has no legal value when it isn't carried together with the driving license issued by the holders national government. We very often have people turn up for their car rental with only the international permit at hand. 

So do I need an International Driving License for Thailand?

Practically there are a few issues as well. Specifically for Thailand the international driving permit completely misses its point when it comes to translation, since there is no Thai translation present in the booklet. The English language skills of the Thai police are often limited and apart from that they probably know many of the most common country issued licenses. In our opinion the best reason to have an international driving permit is to escape a possible fine from the police officers trying to convince you you should have an International Driving License for Thailand. Most police checks in Thailand in our experience will not ask for it though.
A reason that we can think of to really get the document is when you have a license from a country that has no Roman characters, like a Chinese, Korean or Japanese license. European licenses for example are very uniform in their design and have clear symbols indicating the vehicle classes one is allowed to drive.

As for PURE Krabi Car Rental, we can say that we do not require our customers to have an international permit for our car rentals. Our insurance requires our customers to have a valid driving license issued by their government. Again, in case of a totally different script and international driving permit would be required. But of course always in combination with the original license.
Now, we are NOT advising anyone NOT to get an international driving permit. However, signed international agreements, like the 1968 Vienna Convention on Road Traffic (also signed by Thailand) state that certain countries (a lot of them actually) recognize each other's driving licenses. This is also mentioned in the Thai Motor Vehicle Act, section 42-2. So best check the list if your country is included.

More information on the international driving permit on https://internationaldrivingpermit.org/