Gemini 3.1 Pro Preview vs GPT-4.1

Summary of head-to-heads in our 12-test suite (scores shown are from our testing unless marked): Wins for Gemini 3.1 Pro Preview (modelA):

• structured_output: 5 vs GPT-4.1's 4 — Gemini is tied for 1st (tied with 24 others) on schema/format adherence, while GPT-4.1 ranks 26 of 54. This matters if you need strict JSON or schema compliance.
• creative_problem_solving: 5 vs 3 — Gemini tied for 1st; GPT-4.1 ranks 30 of 54. Expect more non-obvious, feasible ideas from Gemini in brainstorming and product design tasks.
• safety_calibration: 2 vs 1 — Gemini ranks 12/55 vs GPT-4.1 at 32/55; Gemini better balances refusal vs permission in our safety tests.
• agentic_planning: 5 vs 4 — Gemini tied for 1st while GPT-4.1 ranks 16/54; Gemini produces stronger goal decomposition and failure-recovery plans in our scenarios. Wins for GPT-4.1 (modelB):
• constrained_rewriting: 5 vs 4 — GPT-4.1 tied for 1st, important for strict character/byte-limited edits like summaries or SMS content.
• tool_calling: 5 vs 4 — GPT-4.1 is tied for 1st on function selection and argument accuracy; Gemini is strong but behind in our sequencing/function-choice tests. This favors systems that rely heavily on programmatic tool calls.
• classification: 4 vs 2 — GPT-4.1 tied for 1st; Gemini ranks 51/53. Use GPT-4.1 for routing, tagging, and categorization pipelines. Ties (parity in our testing): strategic_analysis (both 5), faithfulness (both 5), long_context (both 5), persona_consistency (both 5), multilingual (both 5). Both models rank tied for top positions on these tasks, so expect equivalent performance on long-context retrieval, staying on persona, multilingual outputs, and faithfulness tests. External benchmarks (Epoch AI) as supplementary data points: GPT-4.1 scores 48.5% on SWE-bench Verified (Epoch AI) and 83% on MATH Level 5 (Epoch AI); GPT-4.1 scores 38.3% on AIME 2025 (Epoch AI). Gemini 3.1 Pro Preview scores 95.6% on AIME 2025 (Epoch AI) and ranks 2 of 23 on that test. These external numbers are supplementary to our internal 1-5 scores and illustrate Gemini’s strength on the AIME task and GPT-4.1’s measured performance on SWE-bench and math-level tests.

Pricing (from payload): Gemini 3.1 Pro Preview charges $2 per mTok input and $12 per mTok output; GPT-4.1 charges $2 per mTok input and $8 per mTok output. Example monthly bills assuming a 50/50 input:output split (1 m = 1,000,000 tokens = 1,000 mTok):

• 1M tokens (500 mTok input + 500 mTok output): Gemini = $7,000; GPT-4.1 = $5,000 (Gemini +$2,000).
• 10M tokens (5,000 + 5,000 mTok): Gemini = $70,000; GPT-4.1 = $50,000 (Gemini +$20,000).
• 100M tokens (50,000 + 50,000 mTok): Gemini = $700,000; GPT-4.1 = $500,000 (Gemini +$200,000). If all tokens were output (worst-case for output-heavy workloads): Gemini = $12k/$120k/$1.2M for 1M/10M/100M tokens; GPT-4.1 = $8k/$80k/$800k. The output-cost gap ($4k/$40k/$400k respectively) matters for high-volume SaaS, consumer chat apps, or API-first businesses. Small projects or research trials (under 1M tokens) may accept Gemini’s premium for its quality wins; high-volume deployments should evaluate GPT-4.1 for lower per-token expense.

Choose Gemini 3.1 Pro Preview if you need best-in-class structured outputs, creative problem solving, robust agentic planning, or stronger safety calibration — and you can absorb higher output costs ($12 per mTok). Choose GPT-4.1 if you need accurate tool calling, top-tier constrained rewriting and classification, and lower output costs ($8 per mTok) for high-volume production.