What Is the Difference Between Burnt and Burned?

'Burned' is the usual past tense of 'burn', but 'burnt' is common in many contexts when the past participle is used as an adjective ("burnt toast"). Both are acceptable forms.

Is it burned out or burnt?

Burned and burnt both work as the past tense and past participle of burn. Both are used throughout the English-speaking world, but usage conventions vary. American and Canadian writers use burned more often, and they use burnt mainly in adjectival phrases such as burnt out and burnt orange.

Is it burnt or burned UK?

In particular, 'burnt' is rare in American English, especially as a verb. So if you're writing for an audience in the USA, you may want to stick with 'burned'. But if you're writing for a UK or Australian audience, 'burnt' is a completely acceptable spelling.