DeepSeek V3.2 vs GPT-5 Mini

We tested 12 internal benchmarks (1-5 scale). Wins/ties summary: GPT-5 Mini wins 2 tests (classification 4 vs 3, safety_calibration 3 vs 2), DeepSeek V3.2 wins 1 test (agentic_planning 5 vs 4), and 9 tests tie. Breakdown by test: - Structured_output: tie (5/5 each). Both models are tied for 1st on our structured-output metric (tied with 24 others), so both are reliable at JSON/schema adherence. - Long_context: tie (5/5 each); both tied for 1st with many models, so retrieval at 30k+ tokens should be robust on either. - Persona_consistency, faithfulness, multilingual, creative_problem_solving, constrained_rewriting, strategic_analysis, tool_calling: ties (scores equal), meaning similar practical behavior on those tasks in our suite. - Classification: GPT-5 Mini 4 vs DeepSeek 3 — GPT-5 Mini ranks tied for 1st on classification (rank 1 of 53 tied with 29 others), so it is the safer pick when routing/categorization accuracy matters. - Safety_calibration: GPT-5 Mini 3 vs DeepSeek 2 — GPT-5 Mini ranks 10 of 55 vs DeepSeek 12, so GPT-5 Mini refused/allowed harmful requests more appropriately in our testing. - Agentic_planning: DeepSeek V3.2 5 vs GPT-5 Mini 4 — DeepSeek ties for 1st (rank 1) while GPT-5 Mini ranks 16 of 54, so DeepSeek is stronger at goal decomposition and failure recovery in our agentic planning tests. External benchmarks (supplementary): GPT-5 Mini scores 97.8% on MATH Level 5 (Epoch AI), 64.7% on SWE-bench Verified (Epoch AI), and 86.7% on AIME 2025 (Epoch AI). We report those external numbers as provided by Epoch AI; DeepSeek has no external scores in the payload.

Costs are materially different. Using a 50/50 split of input/output tokens as an example: DeepSeek V3.2 charges $0.26/mTok input and $0.38/mTok output, so 1M tokens (500k input + 500k output) costs $320. GPT-5 Mini charges $0.25/mTok input and $2.00/mTok output, so the same 1M-token mix costs $1,125. At 10M tokens/month those totals scale to $3,200 (DeepSeek) vs $11,250 (GPT-5 Mini); at 100M tokens/month they scale to $32,000 vs $112,500. Teams doing high-volume inference (>=10M tokens/mo) will see six-figure annual differences and should care about DeepSeek's lower per-token pricing; teams needing multimodal inputs or the safety/classification advantages may accept GPT-5 Mini's higher output cost.

Choose DeepSeek V3.2 if: you run high-volume text-only workloads and need strong agentic planning and long-context support at a much lower cost (input $0.26/mTok, output $0.38/mTok). Choose GPT-5 Mini if: you need multimodal inputs (text+image+file), stronger classification and safety calibration in our tests, or superior performance on third-party math and coding benchmarks (e.g., 97.8% on MATH Level 5, Epoch AI), and you can accept higher output cost ($2.00/mTok).