xAI's Grok 4 Fast cuts reasoning costs by 98%
xAI just launched Grok 4 Fast, a cost-efficient reasoning model packed with a 2M token context window. It matches Grok 4 on key benchmarks while using 40% fewer thinking tokens, slashing overall costs by 98% and taking the top spot on LMArena's Search Arena. It is now completely free for all users.