GPT-5.2 vs Grok 3

Test-by-test summary (our 12-test suite):

• GPT-5.2 wins: safety calibration (score 5 vs Grok 3's 2) — GPT-5.2 is tied for 1st on safety among 55 models in our ranking, so it will more reliably refuse harmful or disallowed requests while allowing legitimate ones. Constrained_rewriting (4 vs 3) — ranks GPT-5.2 rank 6/53, meaning better at tight character/byte compression. Creative_problem_solving (5 vs 3) — GPT-5.2 ties for 1st, so it produces more non-obvious, feasible ideas in our tests.
• Grok 3 wins: structured output (5 vs GPT-5.2's 4) — Grok 3 is tied for 1st in structured output across 54 models, so it’s strongest when JSON/schema adherence is critical.
• Ties (no clear winner): strategic analysis (5/5), tool calling (4/4), faithfulness (5/5), classification (4/4), long context (5/5), persona consistency (5/5), agentic planning (5/5), multilingual (5/5). Where tied, rankings show both models frequently sit at the top (e.g., both tie for 1st in strategic analysis and long context), so either model is viable for those tasks.
• External benchmarks: Beyond our internal scores, GPT-5.2 scores 73.8% on SWE-bench Verified (Epoch AI) and 96.1% on AIME 2025 (Epoch AI). Grok 3 has no external scores in the payload. These external results support GPT-5.2’s strong coding/math performance in our view. What this means for real tasks: choose GPT-5.2 where safety, long-context retrieval (30K+ tokens), high-fidelity creative solutions, or math/coding accuracy matter. Choose Grok 3 when strict schema/JSON output and enterprise extraction pipelines demand the strongest structured-output compliance.

Per the payload, GPT-5.2 costs $1.75 input / $14 output per mTok; Grok 3 costs $3 / $15. Assuming 1 mTok = 1,000 tokens (industry convention), and a 50/50 split of input/output tokens: for 1M tokens/month (1,000 mToks) GPT-5.2 ≈ $7,875 vs Grok 3 ≈ $9,000 (difference $1,125). At 10M tokens/month: GPT-5.2 ≈ $78,750 vs Grok 3 ≈ $90,000 (difference $11,250). At 100M tokens/month: GPT-5.2 ≈ $787,500 vs Grok 3 ≈ $900,000 (difference $112,500). High-volume API customers and cost-sensitive products should note these absolute dollar gaps; for small-scale usage the difference is modest, but at tens of millions of tokens the savings become material.

Choose GPT-5.2 if you need top safety, long-context handling, creative problem solving or the strongest math/coding signals (GPT-5.2 wins 3 vs 1 and has SWE-bench 73.8% and AIME 96.1%). It’s also slightly cheaper per mTok. Choose Grok 3 if your primary requirement is flawless structured output (Grok 3 scores 5 vs GPT-5.2's 4 and is tied for 1st on structured output) or you rely on xAI-specific tooling that depends on strict schema compliance.