
simonwillison.net
May 1, 2026
3 min read
47/100
Summary
DeepSeek has released two preview models in its V4 series: DeepSeek-V4-Pro and DeepSeek-V4-Flash. The Pro model features 1.6 trillion total parameters with 49 billion active, while the Flash model has 284 billion total parameters and 13 billion active, both utilizing a 1 million token context Mixture of Experts architecture under the MIT license.
Key Takeaways
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