GPT-4o-mini vs GPT-5.2

Test-by-test (our 1–5 internal scores unless noted):

• Strategic analysis: GPT-5.2 5 vs GPT-4o-mini 2 — GPT-5.2 wins and is tied for 1st on strategic analysis ("tied for 1st with 25 other models out of 54 tested"), meaning better nuanced tradeoff reasoning for planning and numerical decisions.
• Structured output: both 4 — tie (rank 26 of 54 for each); both are competent at JSON/schema compliance.
• Persona consistency: GPT-5.2 5 vs GPT-4o-mini 4 — GPT-5.2 wins (tied for 1st with 36 others), so it better maintains character and resists prompt injection in our tests.
• Agentic planning: GPT-5.2 5 vs GPT-4o-mini 3 — GPT-5.2 wins (tied for 1st with 14 others), stronger at goal decomposition and failure recovery.
• Constrained rewriting: GPT-5.2 4 vs GPT-4o-mini 3 — GPT-5.2 wins (rank 6 of 53), better at tight compression and length limits.
• Faithfulness: GPT-5.2 5 vs GPT-4o-mini 3 — GPT-5.2 wins (tied for 1st with 32 others), meaning fewer hallucinations in our testing.
• Long context: GPT-5.2 5 vs GPT-4o-mini 4 — GPT-5.2 wins (tied for 1st with 36 others), stronger retrieval and coherence past 30K tokens.
• Classification: both 4 — tie (both tied for 1st with 29 others), comparable for routing and categorization.
• Creative problem solving: GPT-5.2 5 vs GPT-4o-mini 2 — GPT-5.2 wins (tied for 1st), better at novel, feasible idea generation.
• Tool calling: both 4 — tie (rank 18 of 54 for each); both select and sequence functions similarly in our tests.
• Safety calibration: GPT-5.2 5 vs GPT-4o-mini 4 — GPT-5.2 wins (tied for 1st with 4 others), better at refusing harmful requests while permitting legitimate ones.
• Multilingual: GPT-5.2 5 vs GPT-4o-mini 4 — GPT-5.2 wins (tied for 1st with 34 others), stronger non‑English parity. External benchmarks (Epoch AI) as supplementary datapoints: GPT-5.2 scores 73.8% on SWE-bench Verified (Epoch AI) and 96.1% on AIME 2025 (Epoch AI, tying it as the top AIME performer in our payload). GPT-4o-mini scores 52.6% on MATH Level 5 and 6.9% on AIME 2025 (Epoch AI). These external results align with the internal picture: GPT-5.2 excels at difficult math, verified code resolution, long-context and safety; GPT-4o-mini is capable on classification and structured outputs but trails on high‑end reasoning and math.

Per‑mTok prices from the payload: GPT-4o-mini input $0.15 / output $0.60; GPT-5.2 input $1.75 / output $14.00. Per million tokens (mTok × 1,000): GPT-4o-mini = $150 input / $600 output; GPT-5.2 = $1,750 input / $14,000 output. Under a 50/50 input-output split the monthly cost is: 1M tokens → GPT-4o-mini $375 vs GPT-5.2 $7,875; 10M → GPT-4o-mini $3,750 vs GPT-5.2 $78,750; 100M → GPT-4o-mini $37,500 vs GPT-5.2 $787,500. If your workload is heavily output‑weighted (e.g., long generated responses), the gap widens because GPT-5.2’s $14/mTok output rate dominates costs. Organizations running high‑volume SaaS, chat, or consumer apps should care deeply about this gap; small teams or R&D projects that need the highest reasoning, safety, and long-context fidelity may justify GPT-5.2’s premium.

Choose GPT-4o-mini if you need a practical, multimodal model at very low cost: it supports text+image+file inputs, has a 128k context window, and costs $0.15 input / $0.60 output per mTok — ideal for high-volume chat, consumer apps, and price-sensitive production. Choose GPT-5.2 if your priority is top-tier strategic reasoning, safety calibration, long-context coherence, agentic planning, creative problem solving, or competitive math performance (GPT-5.2 scores 96.1% on AIME 2025 per Epoch AI); accept a substantially higher bill ($1.75/$14 per mTok) for those gains.