@Pe***
most if not all Thai banks list their exchange rate online. If you are transferring in USD (most likely) it will be the Thai bank converting it. I linked Bangkok Bank above. Their rates for USD are good, but 33.
*****
.61 is still a spread of just under 1%. They usually skew to the buy rate. The current Wise rate of 33.53 is 0.66% better.
This is not a big difference or a terrible rate from Bangkok Bank but if you were transferring $25,000 (for a retirement extension, for example), 0.66% of that is $165. Not saying that's an unfair rate, it's competitive with Wise, but it's a lot more than $25. Thai Thai bank will also charge 500B to receive the money.
If you are transferring in THB, you'd look at the exchange rates for your home bank. This is much less common though and rates are usually much worse, the Thai bank rates are competitive with Wise for larger sums.