Thai baht to New Zealand dollars, in your head
One rule, the error band that comes with it, and the point at which it stops being the right rule. Updated from the live rate feed.
Baht to New Zealand dollars. Accurate to within 2.0% at today's rate, which means it reads about 2.0% cheaper than the real price — round up, not down.
The ladder
The middle column is what the rule gives you standing in a market. The right column is the real number, so you can see exactly where the shortcut costs you.
| Thai baht | Rule of thumb | Actual |
|---|---|---|
| ฿5 | NZ$0.25 | NZ$0.255 |
| ฿10 | NZ$0.5 | NZ$0.51 |
| ฿20 | NZ$1 | NZ$1.02 |
| ฿50 | NZ$2.5 | NZ$2.55 |
| ฿100 | NZ$5 | NZ$5.1 |
| ฿200 | NZ$10 | NZ$10.2 |
| ฿500 | NZ$25 | NZ$25.51 |
| ฿1,000 | NZ$50 | NZ$51.02 |
| ฿2,000 | NZ$100 | NZ$102 |
Going the other way
Useful at the ATM, where you choose an amount in New Zealand dollars and want to know what lands in your hand.
| New Zealand dollars | Thai baht |
|---|---|
| NZ$1 | ฿19.6 |
| NZ$5 | ฿98 |
| NZ$10 | ฿196 |
| NZ$20 | ฿392 |
| NZ$50 | ฿980 |
| NZ$100 | ฿1,960 |
What catches people out in Thailand
Baht are quoted in whole numbers almost everywhere, and street prices cluster on 20, 50 and 100. If a menu shows decimals you are probably in a tourist restaurant.
When this rule stops working
Rules of thumb rot quietly. This one holds while the rate stays roughly between 19.5 and 20.5 THB to the New Zealand dollar. Outside that band a different divisor becomes the better one to memorise. We regenerate this page from the live rate feed, so the date above tells you how fresh the number is — if you are reading this a long way after August 2026, check it before you rely on it.
Or skip the arithmetic entirely
RoamRate does this conversion with no signal, in one hand, on a number pad built for a thumb. Free for NZD; THB and 150+ other currencies unlock for $4.99, once.
Download on the App Store