Gemini 3.1 Pro vs Gemini 3.8 Flash
At a Glance
| Compare |  Gemini 3.1 ProGoogle DeepMind | Gemini 3.8 FlashGoogle DeepMind |
|---|---|---|
| Intelligence, Cost, and Efficiency | ||
| IntelligenceHigher is better · MM Intelligence v4.4 | #9 of 5782.1 score · 3/3 sources · complete | #4 of 5790.0 score · 3/3 sources · complete |
| CostLower is better · Published-token output estimate | #18 of 27$0.161 per LiveBench case | #17 of 27$0.160 per LiveBench case |
| EfficiencyHigher is better · MM Efficiency v1.9 | #8 of 2754.6 score · 3/3 sources · complete | #7 of 2758.5 score · 3/3 sources · complete |
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $2.00Google AI ↗ · Aug 29, 2026 | $0.75Google AI ↗ · Sep 2, 2026 |
| Output priceFrom · USD / 1M tokens | $12.00Google AI ↗ · Aug 29, 2026 | $3.75Google AI ↗ · Sep 2, 2026 |
| Context windowMaximum documented tokens | 1,049K | 1,049K |
| Model facts checked | Aug 29, 2026View model evidence → | Sep 2, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
| Benchmark | Gemini 3.1 Pro | Gemini 3.8 Flash |
|---|---|---|
| ARC-AGI-1verified-v1-302d8267c052 · verified_score · leader | 98.0099% of row best · percent · Gemini 3.1 Pro (Preview) | 98.50100% of row best · percent · Gemini 3.8 Flash (High) |
| ARC-AGI-2verified-v2-bca68e12cc9a · verified_score · leader | 77.0886% of row best · percent · Gemini 3.1 Pro (Preview) | 89.17100% of row best · percent · Gemini 3.8 Flash (High) |
| LMArena Agent Arenaagent-2026-10-16-a64ca3b12b6e · outcome_score · leader | -4.0093% of row best · score · Gemini 3.1 Pro Preview; 95% CI [-5.35690873, -2.63856355]; sessions 87236; observations 2815597; rank 39 | 3.75100% of row best · score · Gemini 3.8 Flash (High); 95% CI [2.64957678, 4.84993702]; sessions 37692; observations 5316787; rank 15 |
| LMArena Vision Arenavision-2026-10-09-a64ca3b12b6e · arena_rating · leader | 1,296.2099% of row best · rating · gemini-3.1-pro-preview; 95% CI [1291.04958388, 1301.35691905]; votes 46320; rank 22 | 1,314.08100% of row best · rating · gemini-3.8-flash-high; 95% CI [1303.54395703, 1324.61562115]; votes 3792; rank 8 |
| LiveBench2026-06-25-90f8d44da965 · overall · leader | 81.66100% of row best · percent · gemini-3.1-pro-preview-high · 13,380 output tokens / case | 80.8599% of row best · percent · gemini-3.8-flash-high · 42,786 output tokens / case |
| ToneBench2026-10-17-10-task-e9c76358afb2 · overall_score · unverified | 70.99100% of row best · points · Gemini 3.1 Pro (high thinking) · 10,029 output tokens / case | 70.2299% of row best · points · Gemini 3.8 Flash (high thinking) · 20,369 output tokens / case |
| Overall ResultCounted from the protocol-matched rows above | 1 benchmark win | 4 benchmark winsOverall lead |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Quality Versus Estimated Output Cost
Side-by-Side Facts
| Field | Gemini 3.1 Pro | Gemini 3.8 Flash |
|---|---|---|
| Developer | Google DeepMind | Google DeepMind |
| Family | Gemini 3 | Gemini 3 |
| Model | Gemini 3.1 Pro | Gemini 3.8 Flash |
| Version | Gemini 3.1 Pro | Gemini 3.8 Flash |
| Lifecycle | preview | active |
| Released | Unknown | 2026-09-02 |
| Knowledge cutoff | Unknown | Unknown |
| Input modalities | Text, Image, Video, Audio, Document | Text, Image, Video, Audio, Document |
| Output modalities | Text | Text |
| Context window | 1,049K | 1,049K |
| Total parameters | Unknown | Unknown |
| Active parameters | Unknown | Unknown |
| License | Unknown | Unknown |
| Open weights | No | No |
| API available | Yes | Yes |
| Self-hostable | No | No |
| Provider access | Google AI (Standard), Google Gemini (Standard) | Google AI (Standard), Google Gemini (Standard) |
| Capabilities | chat, generation, reasoning, tools | chat, code_execution, computer_use, generation, reasoning, structured_outputs, tools |
Gemini 3.1 Pro Capabilities
Gemini 3.8 Flash Capabilities
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Primary Evidence
Sources and Freshness
Questions
Gemini 3.1 Pro vs Gemini 3.8 Flash FAQs
Is Gemini 3.1 Pro or Gemini 3.8 Flash better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Gemini 3.1 Pro and Gemini 3.8 Flash, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Gemini 3.1 Pro or Gemini 3.8 Flash?+
Gemini 3.1 Pro is $2.00 and Gemini 3.8 Flash is $0.75 per million tokens, so Gemini 3.8 Flash is cheaper on this metric. Gemini 3.1 Pro is $12.00 and Gemini 3.8 Flash is $3.75 per million tokens, so Gemini 3.8 Flash is cheaper on this metric.
Which has a larger context window, Gemini 3.1 Pro or Gemini 3.8 Flash?+
Both models have the same sourced context window: 1,048,576 tokens each.
Which performs better in benchmarks, Gemini 3.1 Pro or Gemini 3.8 Flash?+
Gemini 3.8 Flash leads the current overall benchmark count. The result uses 5 protocol-matched benchmarks from 3 publishers; it is not a universal quality score.
Can Gemini 3.1 Pro or Gemini 3.8 Flash be self-hosted?+
Both models have the same sourced self-hosting status: unsupported. Gemini 3.1 Pro is not marked open weight; Gemini 3.8 Flash is not marked open weight.
Can Gemini 3.1 Pro and Gemini 3.8 Flash understand images?+
Gemini 3.1 Pro is documented with image input; Gemini 3.8 Flash is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Gemini 3.1 Pro or Gemini 3.8 Flash?+
Both models have the same sourced maximum output: 65,536 tokens each.
Do Gemini 3.1 Pro and Gemini 3.8 Flash support reasoning and tool use?+
Gemini 3.1 Pro: reasoning, tool calling, and image input. Gemini 3.8 Flash: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, Gemini 3.1 Pro or Gemini 3.8 Flash?+
Gemini 3.1 Pro has 2 sourced provider routes; Gemini 3.8 Flash has 2, a tie.
Which offers better value, Gemini 3.1 Pro or Gemini 3.8 Flash?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.