GPT-4.1 Nano vs Grok 4.1 Fast

Summary of head‑to‑head results in our 12‑test suite: Grok 4.1 Fast wins 6 tests, GPT‑4.1 Nano wins 1, and 5 tests tie. Detailed walk‑through (scores shown as modelA vs modelB, "in our testing"):

• Multilingual: 4 (Nano) vs 5 (Grok). Grok wins and ranks "tied for 1st with 34 other models out of 55 tested," so expect stronger non‑English parity in real tasks.
• Persona_consistency: 4 vs 5 — Grok wins and is tied for 1st, meaning it better maintains character/guardrails in multi‑turn persona scenarios in our tests.
• Long_context: 4 vs 5 — Grok wins and is tied for 1st; this aligns with its 2,000,000 token context window versus Nano's 1,047,576 and matters for retrieval over 30K+ tokens.
• Classification: 3 vs 4 — Grok wins and is tied for 1st (classification rank tied with 29 others), so routing and label accuracy favored Grok in our tests.
• Strategic_analysis: 2 vs 5 — Grok wins decisively and is tied for 1st; expect better nuanced tradeoff reasoning in finance/strategy prompts.
• Creative_problem_solving: 2 vs 4 — Grok wins (rank 9 of 54), showing more feasible, non‑obvious idea generation in our suite.
• Safety_calibration: 2 vs 1 — GPT‑4.1 Nano wins here (Nano rank 12 of 55 vs Grok rank 32 of 55), meaning Nano was more likely to refuse harmful requests while allowing legitimate ones in our tests. Ties (identical scores): structured output 5/5 (both tied for 1st), constrained rewriting 4/4 (rank 6 of 53 for both), tool calling 4/4 (rank 18 of 54 for both), faithfulness 5/5 (both tied for 1st), and agentic planning 4/4 (rank 16 of 54 for both). These ties indicate parity on JSON/schema compliance, concise compression, function selection/argument accuracy, sticking to sources, and goal decomposition in our testing. Additional math benchmarks: GPT‑4.1 Nano scores 70% on MATH Level 5 and 28.9% on AIME 2025 according to Epoch AI; Grok 4.1 Fast has no MATH/AIME scores reported in the payload. These external math results are supplementary to our internal suite and show Nano's relative math performance on those datasets.

Costs per 1,000 tokens (mTok): GPT-4.1 Nano input $0.10 + output $0.40 = $0.50/mTok; Grok 4.1 Fast input $0.20 + output $0.50 = $0.70/mTok. At 1M tokens/month (1,000 mTok) that is $500 (Nano) vs $700 (Grok) — a $200/month gap. At 10M tokens/month it's $5,000 vs $7,000 (a $2,000 gap). At 100M tokens/month it's $50,000 vs $70,000 (a $20,000 gap). High‑volume SaaS providers, analytics pipelines, and any deployment with sustained multi‑million token usage should care about this gap; companies needing multilingual, strategic reasoning, or 2M token context may accept Grok's premium. Low‑latency chat, cost‑constrained products, and early prototypes will favor GPT‑4.1 Nano for direct dollar savings.

Choose GPT-4.1 Nano if: you need the lower per‑token cost ($0.50/mTok vs $0.70/mTok), lower latency, better safety calibration in our tests, or better-reported math scores (70% MATH Level 5, 28.9% AIME 2025 by Epoch AI). It’s the practical choice for high‑volume chat, cost‑sensitive SaaS, and safety‑strict flows. Choose Grok 4.1 Fast if: you need top multilingual quality, the largest long‑context support (2,000,000 tokens), stronger strategic analysis, creative problem solving, classification, or persona consistency (Grok wins 6 of 12 benchmarks). It’s the better choice for international customer support, deep research over very long context, and complex decision‑making despite a higher token cost.