What's currently the 'smartest' language model?

Looking for an "AI" that would tackle my day-to-day issues that are not related to programming, for example acting as a personal assistant / life coach, creating lesson plans for classes I teach at school, explaining how things work and teaching me new skills effectively, etc.

I need it to be able to consider web search options for more comprehensive answers.

Doesn't have to be free, as I'd be happy to pay if it's truly worth it.

So far I've tried:

1. Most common options at Poe, including Claude Sonnet 3.5, GPT4o and others. The issue here is that I'm not seeing which one is actually smarter and which one hallucinates more.
2. Perplexity
3. Phind
4. Gemini
5. Bing AI

I have never had a GPT4 subscription so I might consider that if it's objectively the best option.

What can you recommend? 🙂