DeepSeek

The Chinese model that sent shockwaves through Silicon Valley, and it hasn't slowed down since. DeepSeek V4 (spring 2026) sits close to the top models on reasoning and code, while the API costs pennies next to everyone else. The chat on their website is completely free - open it and start typing. The weights are open, so with serious hardware you can run it locally, and plenty of other services host it too. The elephant in the room: your conversations go through Chinese servers, so don't paste your startup's secret sauce in there. For general research, learning and coding questions where privacy isn't critical, it's an absurdly good free option.

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