GPT-5.1 Codex Mini: benchmark scores, price and ranking

GPT-5.1 Codex Mini from OpenAI ranks #328 of 743 LLMs on the LLMs Tiger aggregate benchmark score (48.7), based on 2 benchmark results captured up to 2026-10-13.

Organisation: OpenAI
Type: Fast / low-cost (flash) model
Open weights: No
Released: 2025-11-12 (source: epoch)
Context window: 400,000 tokens
Cheapest API price: $0.250 in / $2.00 out per million tokens (via azure, observed 2026-10-13T21:47Z)
Aggregate rank: #328 of 743 (score 48.7)

Across the 2 benchmarks where at least ten models are scored, GPT-5.1 Codex Mini is in the top 10% on 0 and in the top half on 1.

Its cheapest listed input price, $0.250 per million tokens, is lower than that of 64% of the 427 models with a listed price.

GPT-5.1 Codex Mini benchmark results

GPT-5.1 Codex Mini benchmark scores, ranked against all models measured on each benchmark
Benchmark	Score	Rank	Source	Captured
Terminal-Bench 2.0	61.6%	#3 of 28	Epoch AI Benchmarking Hub	2026-10-13
WebDev Arena	1,247	#59 of 67	Epoch AI Benchmarking Hub	2026-10-13

About GPT-5.1 Codex Mini

GPT-5.1 Codex Mini is a smaller, lower-cost model from OpenAI. It was released on 2025-11-12, according to Epoch AI. It accepts up to 400,000 tokens of input at once. The cheapest API listing we track charges $0.250 per million input tokens and $2.00 per million output tokens, through azure. We hold 2 benchmark results for it across 1 area, and none is in the top tenth of its board.

Where GPT-5.1 Codex Mini stands

On our aggregate score, GPT-5.1 Codex Mini is #328 of 743 ranked models, around the middle of the table. Its score is 48.7; the scale is centred on 50, so it sits 1.3 points below the typical model. That beats 56% of the ranked field. Among the 88 ranked OpenAI models it is #43. The next one up is gpt-5.2-chat-latest-20260210 at 49.1. The next one down is chatgpt-4o-latest (2025-02-15) at 48.6.

GPT-5.1 Codex Mini, benchmark by benchmark

Terminal-Bench 2.0 puts GPT-5.1 Codex Mini at 61.6%, #3 of 28. That beats 89% of the models tested, but 7.9 points short of Gemini 3 Pro Preview (69.4%). The results either side are GPT-5.2 Codex (66.5%) and GPT-5.1-Codex-Max (60.4%). It covers real terminal tasks (agent + model). The board median is 37.3%, so GPT-5.1 Codex Mini is 24.3 points above it. Source: Epoch AI Benchmarking Hub, captured 2026-10-13.

WebDev Arena is a weak spot. GPT-5.1 Codex Mini scores 1,247, #59 of 67, behind 87% of the models measured. The leader, Claude Opus 5.5 (max), reaches 1,820. It covers building web apps, crowd-voted (Elo). The board median is 1,433, so GPT-5.1 Codex Mini is 186 points below it. Source: Epoch AI Benchmarking Hub, captured 2026-10-13.

Strengths and weaknesses

Software engineering: solid, ahead of 51% of the field on average across 2 benchmarks. Its best board here is Terminal-Bench 2.0 (#3 of 28) and its weakest is WebDev Arena (#59 of 67).

Price and value

The median input price across the 427 priced models is $0.500 per million tokens, so GPT-5.1 Codex Mini costs less than the typical listing. Models that score within 1.5 points or better and cost less: Qwen2.5-Coder-7B-Instruct ($0.010, 49.5), DeepSeek V4.1 Flash (high) ($0.010, 48.9), DeepSeek V4 Flash 0731 (max) ($0.016, 53.1). Similar scores cost more on DeepSeek-V3.2 (Thinking; Fireworks) ($0.259) and DeepSeek-V3.2 ($0.259).

Release history

The OpenAI model released before it was GPT-5.1 Codex on 2025-11-12, which scores 50.7. The next one was GPT-5.1 (high) on 2025-11-12, at 52.7.

Reading these numbers

The 2 scores on this page come from 1 source: Epoch AI Benchmarking Hub (2). No official leaderboard supplied any of them, so treat them as third-party measurements. With 2 results the aggregate rank can move a lot when one new score arrives.

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