Gemini 2.5 Pro vs GPT-4.1

Across our 12-test suite, the head-to-head wins are split and most tests are ties (8 ties). Detailed comparison with scores and rank context:

• Gemini 2.5 Pro wins structured_output 5 vs 4 (Gemini: tied for 1st with 24 others out of 54; GPT-4.1: rank 26 of 54). This matters when you need strict JSON/schema compliance.
• Gemini wins creative_problem_solving 5 vs 3 (Gemini: tied for 1st with 7 others; GPT-4.1: rank 30 of 54). Expect more non-obvious, feasible ideas from Gemini in our tests.
• GPT-4.1 wins strategic_analysis 5 vs 4 (GPT-4.1: tied for 1st with 25 others; Gemini: rank 27 of 54). For nuanced tradeoff reasoning with numbers, GPT-4.1 scored higher.
• GPT-4.1 wins constrained_rewriting 5 vs 3 (GPT-4.1: tied for 1st with 4 others; Gemini: rank 31 of 53). For tight character-limit compression and precise rewrites, GPT-4.1 is stronger. Ties (identical scores): tool_calling (5), faithfulness (5), classification (4), long_context (5), safety_calibration (1), persona_consistency (5), agentic_planning (4), multilingual (5). Notably both models top out on long_context, tool_calling, faithfulness and multilingual in our rankings (many models share top scores), but both score poorly on safety_calibration (1/5; rank ~32 of 55). External benchmarks (Epoch AI): on SWE-bench Verified Gemini scores 57.6% vs GPT-4.1's 48.5% (Epoch AI), favoring Gemini for real GitHub issue resolution. On AIME 2025 (Epoch AI) Gemini scores 84.2% vs GPT-4.1's 38.3%, a substantial gap favoring Gemini on that math olympiad measure. GPT-4.1 has a math_level_5 score of 83% (Epoch AI) where Gemini has no reported math_level_5 in the payload; use those external measures as supplementary context.

Costs per mTok: Gemini 2.5 Pro input $1.25, output $10; GPT-4.1 input $2, output $8. Example (assumes 50/50 input/output split):

• 1M tokens (1,000 mTok): Gemini = $5,625 (500 mTok input = $625; 500 mTok output = $5,000). GPT-4.1 = $5,000 (500 mTok input = $1,000; 500 mTok output = $4,000). GPT-4.1 saves $625/month.
• 10M tokens (10,000 mTok): Gemini = $56,250; GPT-4.1 = $50,000. Savings with GPT-4.1 = $6,250/month.
• 100M tokens (100,000 mTok): Gemini = $562,500; GPT-4.1 = $500,000. Savings = $62,500/month. Who should care: any high-volume generator of long outputs (e.g., document generation, long-chat transcripts) will pay materially more with Gemini because its output cost is $10/mTok vs $8/mTok. Workloads that are input-heavy (many retrieval tokens) benefit from Gemini's cheaper input ($1.25 vs $2).

Choose Gemini 2.5 Pro if you: need best-in-class structured output and creative problem generation, require wider modality support (text+image+file+audio+video->text), or run retrieval/input-heavy workloads (its input cost is $1.25/mTok). Choose GPT-4.1 if you: prioritize nuanced strategic analysis and constrained rewriting, want overall lower output-costs ($8 vs $10/mTok) for high-volume generation, or prefer the slightly better cost profile on output-dominant use cases.