Gemma 4 31B vs o4 Mini

Overview: across our 12-test suite Gemma 4 31B wins 3 categories (constrained rewriting, safety calibration, agentic planning), o4 Mini wins 1 (long context), and 8 are ties. Details: 1) Constrained rewriting: Gemma 4 31B scores 4 vs o4 Mini 3; Gemma ranks 6 of 53 (shared) vs o4 Mini rank 31 — Gemma is measurably better at tight-character compression. 2) Safety calibration: Gemma 2 vs o4 Mini 1; Gemma ranks 12/55 (tied) vs o4 Mini 32/55 — Gemma is more likely to refuse harmful requests correctly in our tests. 3) Agentic planning: Gemma 5 vs o4 Mini 4; Gemma ties for 1st (with 14 others) while o4 Mini sits at rank 16 — Gemma produces stronger goal decomposition and failure-recovery in our scenarios. 4) Long context (30K+ retrieval): o4 Mini wins 5 vs Gemma 4; o4 Mini ties for 1st (with 36 others) while Gemma is down at rank 38 of 55 — expect better retrieval accuracy from o4 Mini on very large contexts. 5) Structured output, tool calling, faithfulness, classification, persona consistency, multilingual, creative problem solving, strategic analysis: both models tie (usually 4–5), and several ties are top-ranked — e.g., structured output is tied for 1st with 24 other models for both. External math benchmarks: o4 Mini scores 97.8% on MATH Level 5 and 81.7% on AIME 2025 (Epoch AI), which supports its strong performance on math/competition-style problems; Gemma has no external math scores in the payload. Operational notes: both models support multimodal inputs; o4 Mini’s quirks include using reasoning tokens and a min max completion token requirement (min_max_completion_tokens: 1000), which affects prompt and token planning.

Per-mTok prices: Gemma 4 31B is $0.13 input / $0.38 output; o4 Mini is $1.10 input / $4.40 output. Using a 50/50 input-output split as a practical example: 1M total tokens (500k input + 500k output) costs $255 on Gemma (0.13500 + 0.38500 = $65 + $190) vs $2,750 on o4 Mini (1.10500 + 4.40500 = $550 + $2,200). Scale: 10M tokens ≈ $2,550 (Gemma) vs $27,500 (o4 Mini); 100M tokens ≈ $25,500 vs $275,000. High-volume deployments, consumer apps, and teams optimizing latency-per-dollar should care deeply — Gemma cuts per-token spend by ~91.4% (priceRatio 0.08636) compared with o4 Mini in this example.

Choose Gemma 4 31B if: you need top agentic planning, structured outputs, better constrained-rewriting and safety calibration in our tests, and far lower per-token cost (input $0.13 / output $0.38). Ideal for high-volume apps, multimodal assistants, and teams optimizing TCO. Choose o4 Mini if: your priority is maximal long-context retrieval accuracy (long context score 5) or competitive external math performance (MATH Level 5 97.8%, AIME 2025 81.7% per Epoch AI) and you can absorb substantially higher token costs (input $1.10 / output $4.40) and accommodate its completion-token quirks.