I think the main competitor to OpenAI's free tier is Google Search's AI Overview powered by Gemini 3.5 Flash-Lite. OpenAI's free tier needs to be notably better than that for people to bother. There's also Gemini 3.6 Flash with a generous free tier.
I'm getting all my questions (3-10 each evening) answered by "Gemini Pro Extended" in the free tier, sometimes with PDFs or photos attached. I wouldn't bother with anything "free" below that, unless I'm agentic coding or something.
Are you certain they are the correct answers? No other AI tool halucinations so confidently for me as does Gemini. And I get them across so many topics.
Yes, but I do instruct it to give me the explanations. Maybe that helps.
Also had a terrible experience with Gemini with codibg: it would just show me trimmed diff (to show the changes it made), then........ commit the actually trimmed contents to the original files, discarding everything that was in between.