MModelspectraIndependent AI Model Intelligence
Head-to-head · Updated 2026-09-08
Model Comparison · Head to Head

Gemini 3.1 Pro vs GPT-5.6 Sol

Gemini 3.1 Pro wins on Overall, Multimodal; GPT-5.6 Sol wins on Coding. Every numeric field is compared below, with a worked monthly-cost example and a pick rule for each use case.

VendorGoogle / OpenAI
Data fields15+ dimensions
Updated2026-09-08
Read~9 min
01

Verdict at a glance

Bottom line: Choose Gemini 3.1 Pro when long-context reliability, lower refusal matter most; choose GPT-5.6 Sol when its stronger dimensions is the priority.

Choose Gemini 3.1 Pro if you…

  • Native audio and video
  • Strong scientific computing
  • Largest 2M context
  • Search integration
  • Best for: Multimodal, Scientific reasoning, Audio & video

Choose GPT-5.6 Sol if you…

  • Enhanced reasoning
  • Strong code generation
  • o-series architecture
  • Best for: Reasoning-heavy tasks, Coding, Math
02

Head-to-head aggregate scores

Scores are 0–100, aggregated from public benchmark information and independently weighted across three leaderboards. Rank is out of 22 tracked models.

Gemini 3.1 Pro Higher overall
Google · #3 overall
Overall83
Coding74
Multimodal92
VS
GPT-5.6 Sol
OpenAI · #11 overall
Overall72
Coding88
Multimodal80

Aggregated from public sources and independently weighted; methodology on the Terms page. Scores within 3 points are treated as statistically tied.

03

Specs & pricing — every field side by side

List API prices in USD per 1M tokens. The highlighted cell is the stronger value/capability on that row.

DimensionGemini 3.1 ProGPT-5.6 SolVerdict
VendorGoogle (US)OpenAI (US)Different vendors
Released2026.052026.07GPT-5.6 Sol is newer
Overall (rank)83 · #372 · #11Gemini 3.1 Pro +11
Coding74 · #988 · #3GPT-5.6 Sol +14
Multimodal92 · #280 · #11Gemini 3.1 Pro +12
Context window2M1.05MGemini 3.1 Pro larger
Max output128K128KTie
Effective-context9288Gemini 3.1 Pro more reliable
Input $/1M$2$5Gemini 3.1 Pro cheaper
Output $/1M$12$30Gemini 3.1 Pro cheaper
Cache discountnone50% offGPT-5.6 Sol deeper
Speed~60 tok/s~25 tok/sGemini 3.1 Pro faster
TTFT0.7s2.0sGemini 3.1 Pro snappier
Function calling7893GPT-5.6 Sol ahead
Refusal rate~12%~14%Gemini 3.1 Pro less restrictive
English9092GPT-5.6 Sol
Chinese7574Gemini 3.1 Pro
Modalitiestext, image, audio, videotext, imagedifferent coverage
Open weightsNoNoBoth closed
Fine-tuningYesNo
Free tierGemini App free with limited quota; API free tier availableNo free API tier
SOC2 / no-trainyes / yesyes / yes
Private deploymentNoNoNeither

Fields drawn from vendor public documentation and the Modelspectra 22-model dataset; speed varies with network, concurrency and prompt length. Verify current pricing before purchase.

04

Dimension-by-dimension analysis

Reasoning & overall intelligence

Gemini 3.1 Pro leads the overall aggregate by 11 points (83 vs 72). That is a meaningful, not marginal, edge on hard, multi-step reasoning, while GPT-5.6 Sol remains a strong generalist that is not out of its depth on routine work.

Agentic coding

This is a clear gap: GPT-5.6 Sol scores 88 against 74. On multi-file edits, SWE-style tickets and long-horizon agent loops GPT-5.6 Sol needs fewer correction turns; Gemini 3.1 Pro is still competent for scripts and assisted completion but trails as task complexity rises.

Multimodal

Gemini 3.1 Pro leads multimodal 92 vs 80. A concrete modality difference: Gemini 3.1 Pro additionally handles audio, video.

Speed & latency

Gemini 3.1 Pro is faster in interactive use: ~60 tok/s with 0.7s TTFT versus ~25 tok/s with 2.0s TTFT (about 2.4× the throughput). For conversational UIs where perceived responsiveness drives retention, that edge is a real product factor even when raw reasoning is lower.

Context: window vs usable recall

Nominal windows are 2M for Gemini 3.1 Pro and 1.05M for GPT-5.6 Sol. Effective-context scores point the same way as window size — Gemini 3.1 Pro is ahead on usable recall (92 vs 88), so prefer it for long-document work where details cannot be missed.

Price & total cost

Gemini 3.1 Pro is the cheaper API at $2/$12 versus GPT-5.6 Sol at $5/$30 per 1M input/output tokens — list input is about 2.5× lower. Cache discounts (GPT-5.6 Sol 50%) shift the effective bill, worked out below.

Chinese vs English

English: Gemini 3.1 Pro 90 vs GPT-5.6 Sol 92. Chinese: 75 vs 74. Both are US-based models; for Chinese-first workloads also compare domestic models on the leaderboard.

Tool use & ecosystem

Function-calling score: Gemini 3.1 Pro 78 vs GPT-5.6 Sol 93, so GPT-5.6 Sol has the edge on structured tool use. Fine-tuning is available from Gemini 3.1 Pro. Factor in existing SDK/plugin familiarity — switching cost often outweighs a few-point tool-use gap.

05

Cost worked example — same workload, real token math

Assume a production workload of 100M input + 30M output tokens per month, with 90% of input tokens served from cache. Figures use public list prices.

Scenario · per monthGemini 3.1 ProGPT-5.6 SolGap
List priceno cache applied$560100M in × $2  +  30M out × $12$1,400100M in × $5  +  30M out × $302.50×gap
With caching90% of inputs cache-hit$560no published cache discount$1,17590M cached in × $2.5  +  10M in × $5  +  30M out × $302.10×gap

Illustrative model; your input/output mix and cache-hit ratio change the result. Prices are list rates before any enterprise agreement.

06

Decision tree

IF the workload is agentic or multi-file coding and a wrong first pass is expensive  →  choose GPT-5.6 Sol (coding 88 vs 74).
IF you serve real-time users and latency is a product KPI  →  choose Gemini 3.1 Pro (~60 tok/s, 0.7s TTFT).
IF you are cost-driven at scale on routine, high-volume workloads  →  choose Gemini 3.1 Pro ($$2/$$12 per 1M in/out).
IF long-document recall has to be near-perfect  →  choose Gemini 3.1 Pro (effective context 92 vs 88).
07

Frequently asked questions

Is GPT-5.6 Sol worth the higher price over Gemini 3.1 Pro?
At list the input rate is 2.5x higher, but cache discounts and output pricing narrow the effective gap. Pay the premium when GPT-5.6 Sol's stronger dimensions protect revenue; for routine volume Gemini 3.1 Pro is the economical pick.
Which is better for agentic coding?
GPT-5.6 Sol is decisively stronger for coding (88 vs 74 on the aggregate). The gap shows on SWE-style multi-file tasks and long agent loops that need fewer correction turns; Gemini 3.1 Pro is fine for routine scripts.
How do costs compare at 100M tokens/month with caching?
At 100M input + 30M output with 90% of inputs cache-hit, Gemini 3.1 Pro is about $560/month and GPT-5.6 Sol about $1,175/month after cache discounts ($560 and $1,400 at list).
Does the bigger context window actually matter?
Nominal windows are Gemini 3.1 Pro (2M) and GPT-5.6 Sol (1.05M), but usable recall follows the effective-context score (92 vs 88). Prefer the higher effective-context model for long-document work where nothing can be missed.
Which one supports fine-tuning?
Gemini 3.1 Pro supports fine-tuning; GPT-5.6 Sol does not at this tier. If you plan to adapt the model to a narrow domain, that is a concrete differentiator.
Which handles multimodal inputs better?
Multimodal scores are 92 (Gemini 3.1 Pro) vs 80 (GPT-5.6 Sol), with modality coverage text/image/audio/video versus text/image. Match the model to the input types your product actually receives.