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Comparison · 2 models · Updated Nov 2, 2026

GPT-5.1 Codex mini vs Grok 4.20 (Non-Reasoning)

Too close to call on our weighted score (GPT-5.1 Codex mini 54, Grok 4.20 (Non-Reasoning) 52). The right pick depends on what you value most.

  1. OpenAI

    GPT-5.1 Codex mini

    Released Nov 13, 2025

    54/100
    • ECI—
    • Price$0.25 / $2.00
    • Context400K
    Full specs Remove GPT-5.1 Codex mini

  2. xAI

    Grok 4.20 (Non-Reasoning)

    Released Mar 9, 2026

    52/100
    • ECI—
    • Price$1.25 / $2.50
    • Context1M
    Full specs Remove Grok 4.20 (Non-Reasoning)

  3. Add a model

    Make it a three-way comparison.

01 — Verdict

Too close to call

It is close. Our weighted score puts them within 2 points (GPT-5.1 Codex mini 54/100, Grok 4.20 (Non-Reasoning) 52/100), so choose by what matters most for your work: GPT-5.1 Codex mini on price and Grok 4.20 (Non-Reasoning) for long inputs. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

  • CapabilityNot enough dataNo independent benchmark covers every model here yet
  • Lowest priceGPT-5.1 Codex miniGPT-5.1 Codex mini $0.688 · Grok 4.20 (Non-Reasoning) $1.56 per 1M tokens (3:1 blend)
  • Longest contextGrok 4.20 (Non-Reasoning)Grok 4.20 (Non-Reasoning) 1,000,000 · GPT-5.1 Codex mini 400,000 tokens
  • Widest inputsGrok 4.20 (Non-Reasoning)GPT-5.1 Codex mini: Text, Images · Grok 4.20 (Non-Reasoning): Text, Images, PDFs
  • Self-hostingNo open weightsBoth are available only through APIs
How the score is built
MeasureWeightGPT-5.1 Codex miniGrok 4.20 (Non-Reasoning)
Price50%5539
Inputs & features30%6070
Context window20%4460
Overall100%54/10052/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

GPT-5.1 Codex mini vs Grok 4.20 (Non-Reasoning) specifications side by side
SpecificationGPT-5.1 Codex miniOpenAIGrok 4.20 (Non-Reasoning)xAI
Capability
Capabilities Index (ECI)——
ECI rank——
Price per million tokens
Input$0.25 (best)$1.25
Output$2.00 (best)$2.50
Cached input—$0.20
Blended (3:1)$0.688 (best)$1.56
Long-context rateSame rateOver 200K: $2.50 / $5.00
Price sourceMedian of 16 providersOfficial xAI API
Limits
Context window400,000 tokens1,000,000 tokens (best)
Max output128,000 tokens (best)30,000 tokens
Inputs and features
TextYesYes
ImagesYesYes
PDFsNoYes
AudioNoNo
VideoNoNo
ReasoningYesNo
Tool callingYesYes
Structured outputNoYes
Availability
WeightsProprietaryProprietary
API model ID—grok-4.20-0309-non-reasoning
API providers16 (best)13
ReleasedNov 13, 2025Mar 9, 2026
Knowledge cutoffSep 30, 2024—
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • GPT-5.1 Codex mini$6.50
  • Grok 4.20 (Non-Reasoning)$17.50
04 — Questions

Which should you choose?

Which is better: GPT-5.1 Codex mini or Grok 4.20 (Non-Reasoning)?

It is close. Our weighted score puts them within 2 points (GPT-5.1 Codex mini 54/100, Grok 4.20 (Non-Reasoning) 52/100), so choose by what matters most for your work: GPT-5.1 Codex mini on price and Grok 4.20 (Non-Reasoning) for long inputs. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, GPT-5.1 Codex mini or Grok 4.20 (Non-Reasoning)?

GPT-5.1 Codex mini is cheaper at $0.25 input / $2.00 output per million tokens (median across 16 API providers). Grok 4.20 (Non-Reasoning) costs $1.25 input / $2.50 output per million tokens (official xAI API price). At a typical mix of three input tokens to one output token, that is $0.688 per million tokens for GPT-5.1 Codex mini versus $1.56 for Grok 4.20 (Non-Reasoning) (2.3× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers both models yet. GPT-5.1 Codex mini has not been scored yet and Grok 4.20 (Non-Reasoning) has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for GPT-5.1 Codex mini and Grok 4.20 (Non-Reasoning) yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Both support tool calling for agent workflows.

Which has the bigger context window?

Grok 4.20 (Non-Reasoning) has the largest context window at 1,000,000 tokens, against 400,000 for GPT-5.1 Codex mini. Maximum output per response: GPT-5.1 Codex mini up to 128,000, Grok 4.20 (Non-Reasoning) up to 30,000 tokens.

Which can read images, PDFs, audio or video?

GPT-5.1 Codex mini accepts text and images; Grok 4.20 (Non-Reasoning) accepts text, images and PDFs. Grok 4.20 (Non-Reasoning) handles the widest range of inputs.

Are any of these open source?

No. GPT-5.1 Codex mini and Grok 4.20 (Non-Reasoning) are proprietary and only available through APIs and apps.

Which is newer?

Grok 4.20 (Non-Reasoning) is the newest, released Mar 9, 2026. GPT-5.1 Codex mini came out Nov 13, 2025. Knowledge cutoff: GPT-5.1 Codex mini Sep 30, 2024.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Nov 2, 2026.

05 — Keep comparing

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