MiniMax launches M3.1 Flash API, a 428B-total/23B-active MoE that ran early on OpenRouter as 'Space Bunny' (community reports)

Verified (fact)

Reddit users shared this information, citing MiniMax's announcement post and FAQ page. MiniMax has released M3.1 Flash via API. The company said 'Space Bunny', an unnamed model that appeared on OpenRouter in late September, was an early version of it. According to users, the anonymous model held the top spot on OpenRouter for about 10 days before disappearing on October 5. Most official announcements left out the parameter count, but the FAQ lists 428B total and 23B active. The model has a 1-million-token context window and adjustable thinking effort, and it accepts text, image, and video input. API pricing per million tokens is $0.15 for input, $0.60 for output, and $0.015 for cache reads. Weights are scheduled for release on October 23.

Needs fact-check (claim)

Per MiniMax's announcement: one-third the cost of M3 and three times the speed. Automation-Bench 62%, ALE 30%, DeepSWE 74%, BabyVision 91%. MiniMax's own table shows the model ahead of Opus 5 on Automation-Bench but behind it on Terminal Bench, 38.1 vs. 51.8. Users also pointed out that the announcement lists different DeepSeek scores in the body text (77.0) and in the table (74.2).

Why it matters (interpretation)

The identity of an anonymous model that topped OpenRouter usage is now known. It is a low-cost API with only 23B active parameters, and its weights will follow in three days. That makes it a candidate teams evaluating local or in-house deployment can compare right away. However, all benchmarks are MiniMax's own figures, and the numbers don't match even within the announcement, so it is better to wait for independent evaluations.

Sources

• Community MiniMax M3.1 Flash released, Space Bunny was an early version, weights Oct 23 Reddit
• Community Space Bunny was MiniMax M3.1 Flash. 428B-A23B, weights drop Thursday Reddit
• Community Minimax M3.1 Flash is 428B 23a Reddit

Story thread

1. 2026-10-19 MiniMax reportedly releases 'M3.1 Flash', with model weights due October 23 (community report)
2. 2026-10-19 MiniMax launches M3.1 Flash API, a 428B-total/23B-active MoE that ran early on OpenRouter as 'Space Bunny' (community reports)

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