Comparisons

MiniMax M3.1 Flash vs DeepSeek V4.1 Flash

Same measurement run, same providers, two very different trade-offs — and one place where the vendor-supplied data caveat matters most.

Reviewed

The headline

M3.1 Flash is cheaper per task and scores higher on the composite index. DeepSeek V4.1 Flash is roughly twice as fast and already ships open weights. Neither wins outright, and the interesting differences are in the columns the headline numbers hide.

Same-run comparison

Both rows come from the same Artificial Analysis run on 21 October 2026, so the numbers are comparable to each other.

MetricMiniMax M3.1 FlashDeepSeek V4.1 Flash (Max)
Intelligence Index42.7139.46
Humanity’s Last Exam47.96%39.25%
AA-LCR79.67%84.00%
GDPval-AA47.88%55.00%
Terminal-Bench 4.025.76%26.77%
Automation-Bench (partial)72.52%68.89%
Omniscience accuracy56.2%46.4%
Omniscience hallucination rate92.81%96.46%
Input / output per 1M$0.15 / $0.60$0.30 / $1.20
Cached input per 1M$0.015$0.006
Weighted cost per task$0.22$0.571
Time per task615 s283 s
Median output speed (long prompts)104.7 t/s233.5 t/s
Context window1,000,0001,000,000
WeightsNot publishedOpen, MIT licence, 552B parameters
Release date2026-10-192026-09-10

Where each one wins

M3.1 Flash wins on cost per finished task. $0.22 against $0.571 is a 2.6× difference, and it comes from both a lower token price and a lower reasoning bill. For a workload that runs hundreds of agent tasks a day, this is the number that decides the month.

M3.1 Flash wins on the composite and on automation. The Intelligence Index gap is 42.71 against 39.46, Automation-Bench is 72.52% against 68.89%, and HLE is 47.96% against 39.25%.

M3.1 Flash wins on grounding in hard facts. Accuracy on Omniscience is 56.2% against 46.4%, and the hallucination rate is lower (92.81% against 96.46%). Both numbers are bad in absolute terms — the practical lesson is that neither model should be trusted on long-tail facts without checking.

DeepSeek wins on throughput. A median 233.5 tokens per second against 104.7 is more than twice the speed on long prompts, and it is consistent across prompt lengths. If your bottleneck is wall-clock time on a long agent run, that matters.

DeepSeek wins on open weights. It is MIT licensed with 552B parameters published on Hugging Face, while M3.1 Flash has no public weights at all — see the Ollama page for the three-source check on that.

DeepSeek wins on price-sensitive reverse caching. Its cached input price ($0.006) is lower than M3.1 Flash’s $0.015, though both are far below their standard input rates.

DeepSeek wins on the business-document and professional-knowledge evaluations. GDPval-AA is 55.0% against 47.88%, and AA-LCR is 84.0% against 79.67%.

The caveat that matters here

Artificial Analysis flags M3.1 Flash’s performance and speed data as first-party — supplied by MiniMax — while the same battery for DeepSeek is measured against the provider’s API. In practice this means the speed comparison above is partly a comparison of two vendors’ claims, not of two independently instrumented pipelines.

We are keeping the numbers because they are the best same-run data available, and flagging them so you do not over-read the 2× throughput gap.

Choosing

If you needPick
Lowest cost per agent taskM3.1 Flash
Long-context work on a large codebaseM3.1 Flash (flat price, 1M context, no tier step-up)
Fastest wall-clock completion of long runsDeepSeek V4.1 Flash
Self-hosting or on-premise deploymentDeepSeek V4.1 Flash
Business-document and knowledge workDeepSeek V4.1 Flash
Better grounding on hard factsM3.1 Flash, with verification either way

A note on the “Flash” naming

Both vendors ship a tier called Flash, and several other labs do too. The label means fast and cheap, not weak — but it also means the comparison above is between two specific, dated models rather than between categories. Re-check the numbers when either side ships a new revision.

Next: benchmarks and their reliability, or pricing in detail.

Sources and version notes

Checked October 21, 2026. We label official claims, third-party measurements, our own testing and community reports separately — see the sources policy for what each label means.

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