MiniMax M3.1 Flash in practice: tests and comparisons with DeepSeek V4.1 Flash

A user relays that open weights for MiniMax M3.1 Flash will be released this Friday.

In a single dsh harness turn, M3.1 Flash coded a three.js first-person arena shooter with no external assets, producing about 246K output tokens at 99% cache hit, which the author calls a bigger jump than expected.

A user reports M3.1 Flash results are on par with GLM-5.3-Flash and a large improvement over the previous generation, noting a free first week and half-price first month.

Ran M3.1 Flash in omp to build a realistic WebGPU water scene with a floating camera; averaged ~100 tok/s, slower on prose and faster on code, with a MiniMax Code comparison planned next.

The author says they tested MiniMax M3.1 Flash against DeepSeek V4.1 Flash, Gemini 3.8 Flash and Claude Haiku 5.5, with results in a linked post.

Independent evaluator Artificial Analysis has a model page with its own benchmarks and intelligence index for MiniMax M3.1 Flash.

On the same prompt, DeepSeek V4.1 Flash took 1h28m, 89.5M tokens and $0.54, while M3.1 Flash took 1h6m, 8.1M tokens and $0.22.

A user reports MiniMax M3.1 Flash scores near full marks on old problems but close to zero on new ones, solving old ones in a few thousand tokens while stalling on hard new ones, and questions what such benchmarks measure.

The author used Space Bunny for free via Nous Research's Portal and OpenRouter, calling it blazing fast and strong at complex tasks and coding/agentic workflows with minimal prompting; MiniMax later confirmed it was an early M3.1 Flash.

A Persian post confirms M3.1 Flash is the anonymous Space Bunny, scoring 62.2 on Automation-Bench at one-tenth Opus 5.5's cost, and cites Artificial Analysis at 42 versus DeepSeek's 39.5 and Opus 5.5's 57.6.

A developer built an interactive Three.js seaplane demo with M3.1 Flash via OpenRouter's free endpoint and questions whether the model is worth using.

The author gave Opus 5.5 and MiniMax M3.1 Flash the same neon 1986 Miami scene; Flash came back much cheaper and still held up, leaving the author underwhelmed by Opus.