Grok 3 Mini vs Grok 4.20

Across our 12-test suite Grok 4.20 wins 5 categories, Grok 3 Mini wins 1, and 6 are ties. Detailed per-test interpretation (scores shown are our 1–5 ratings):

• Safety calibration: Grok 3 Mini 2 vs Grok 4.20 1 — Grok 3 Mini wins here in our testing (rank 12 of 55 vs Grok 4.20 rank 32 of 55). Expect Grok 3 Mini to refuse harmful requests more reliably in our safety scenarios.
• Structured output: Grok 3 Mini 4 vs Grok 4.20 5 — Grok 4.20 wins and ranks tied for 1st of 54 on structured output while Grok 3 Mini is rank 26; choose Grok 4.20 when strict JSON/schema compliance matters.
• Strategic analysis: Grok 3 Mini 3 vs Grok 4.20 5 — Grok 4.20 wins and is tied for 1st on strategic analysis; this translates to noticeably better nuanced tradeoff reasoning in our tests.
• Creative problem solving: Grok 3 Mini 3 vs Grok 4.20 4 — Grok 4.20 performs better at generating non-obvious, feasible ideas (rank 9 of 54 for 4.20 vs rank 30 for 3 Mini).
• Agentic planning: Grok 3 Mini 3 vs Grok 4.20 4 — Grok 4.20 wins (rank 16 of 54) for goal decomposition and failure recovery in our agentic planning tests.
• Multilingual: Grok 3 Mini 4 vs Grok 4.20 5 — Grok 4.20 is tied for 1st of 55 on multilingual ability; use it when equivalent non-English quality is required.
• Long context: both 5 — tied for 1st with many models (both tied for 1st of 55); both handle 30K+ token retrieval tasks equally in our tests (note Grok 4.20's context window is 2,000,000 vs 131,072 for Grok 3 Mini in the payload).
• Tool calling: both 5 — both tied for 1st (tool selection, arguments and sequencing were top-tier for both in our tests).
• Faithfulness: both 5 — both tied for 1st, showing similarly low hallucination rates on our faithfulness tasks.
• Persona consistency: both 5 — tied for 1st (both maintain character well in our injection-resistance tests).
• Constrained rewriting: both 4 — tie (rank 6 of 53) for compression-within-limits tasks.
• Classification: both 4 — tie and tied for 1st of 53 in our classification routing tests.

Context and practical meaning: Grok 4.20 is measurably better when outputs must match a schema, when you need multi-step strategic reasoning, or when you support many languages. Grok 3 Mini is preferable if you prioritize safer refusals and much lower cost per token. Both excel at long context, tool calling and faithfulness in our testing.

The payload lists per-mTok prices: Grok 3 Mini input $0.30 / output $0.50 per mTok; Grok 4.20 input $2 / output $6 per mTok. Assuming mTok = 1,000 tokens (so 1M tokens = 1,000 mTok), total cost per mTok is $0.80 for Grok 3 Mini and $8.00 for Grok 4.20. At 1M tokens/month that scales to $800 (3 Mini) vs $8,000 (4.20); at 10M: $8,000 vs $80,000; at 100M: $80,000 vs $800,000. The gap is ~10x. Teams with high-volume usage, tight budgets, or many small requests should care deeply about the difference; teams that need the capabilities where Grok 4.20 wins (structured output, strategic analysis, large multimodal context) may justify the higher spend.

Choose Grok 3 Mini if you: need a low-cost model for high-volume use (total ≈ $0.80/mTok), prioritize safer refusal behavior, want accessible internal reasoning traces, or have budget constraints (1M tokens ≈ $800). Choose Grok 4.20 if you: require top-tier structured output (5/5), stronger strategic analysis and multilingual capability (5/5 across those tests), agentic planning, multimodal inputs, or very large context windows and can afford ~10x higher token costs (1M tokens ≈ $8,000).