I've started tinkering with DeepL which proposes this feature but results are quite off the rails because you cannot provide any context to it.

So well, it was a clear case for an LLM to me. After crafting a good context prompt, I've tried o4-mini from OpenAI and it's results are nearly perfect.

However came business around and I need to be able to this WAY faster, as a ~100ko page will take like a minute to generate, which is way too long for the end user.

I've optimised content a little (sending only html parts that are interesting) but it's still quite slow in the end (more than 10s). I'm thinking about translating html to json and do it back after translation, so it might be faster.

Does anyone do this as well ? Or has any insight of a better performing API/LLM for this problem ?