GPT-4o-mini vs GPT-5 Mini

Head-to-head summary from our 12-test suite: GPT-5 Mini (B) wins 9 tests, GPT-4o-mini (A) wins 2, and 1 ties. Detailed wins: GPT-5 Mini wins structured output (5 vs 4) and is tied for 1st among 54 models for that test — meaning it's among the best for JSON/schema compliance. GPT-5 Mini also wins strategic analysis (5 vs 2), constrained rewriting (4 vs 3), creative problem solving (4 vs 2), faithfulness (5 vs 3), long context (5 vs 4), persona consistency (5 vs 4), agentic planning (4 vs 3) and multilingual (5 vs 4) — many of these are top-ranked (e.g., strategic analysis tied for 1st; long context tied for 1st; multilingual tied for 1st), so expect noticeably stronger reasoning, memory over 30K+ tokens, and non-English parity in real tasks. GPT-4o-mini wins tool calling (4 vs 3) and safety calibration (4 vs 3); tool calling ranks A at 18/54 versus B at 47/54, so GPT-4o-mini is preferable when precise function selection, argument accuracy, and safer refusal behavior are essential. Classification ties (both 4) and are both tied for 1st among peers. External benchmarks (Epoch AI): GPT-5 Mini scores 97.8% on Math Level 5 vs GPT-4o-mini 52.6% (Epoch AI) — a very large gap for competition-level math; GPT-5 Mini also posts 86.7% on AIME 2025 vs GPT-4o-mini 6.9% (Epoch AI). For code-style evaluation, GPT-5 Mini has SWE-bench Verified 64.7% (Epoch AI), while GPT-4o-mini has no SWE-bench score in our payload. In short: GPT-5 Mini delivers higher accuracy and better rankings for complex reasoning, math, long-context retrieval, multilingual output and structured formats; GPT-4o-mini is the cost-efficient choice with stronger tool-calling and slightly better safety calibration in our tests.

Per-1K (mTok) rates: GPT-4o-mini input $0.15 / output $0.60; GPT-5 Mini input $0.25 / output $2.00. Output-only monthly cost at scale: for 1M tokens/month GPT-4o-mini = $600 vs GPT-5 Mini = $2,000; for 10M: $6,000 vs $20,000; for 100M: $60,000 vs $200,000. Including input tokens (example: inputs = 10% of total tokens) raises totals marginally: 1M example totals = $615 (GPT-4o-mini) vs $2,025 (GPT-5 Mini); 10M = $6,150 vs $20,250; 100M = $61,500 vs $202,500. Who should care: teams sending millions of tokens/month (SaaS apps, large chatbots, heavy analytics) will see a 3.33× higher output bill on GPT-5 Mini and should budget accordingly; small-volume projects or high-value reasoning use cases may justify GPT-5 Mini's premium.

Choose GPT-4o-mini if: you need the lowest cost per token, frequent function/tool calling, or safety calibration for interactive apps (output $0.60 / 1K, input $0.15 / 1K). Use cases: high-volume chatbots that call APIs, production assistants that must prioritize cost and robust refusal behavior, or prototypes where budget dominates. Choose GPT-5 Mini if: accuracy, reasoning, math, long-context memory, multilingual parity, or strict structured-output compliance matter (it wins 9 of 12 benchmarks and scores 97.8% vs 52.6% on Math Level 5 — Epoch AI). Use cases: tutoring and assessment, data analysis and reports over 30K+ context, high-stakes decision support, or multilingual/structured-output services where higher per-token cost is justified.