Model Comparison

GPT-5.4 vs Grok-4.20 Beta ReasoningWhich is better in 2026?

Comparing GPT-5.4 and Grok-4.20 Beta Reasoning across benchmarks, pricing, and capabilities.

Verdict: GPT-5.4 vs Grok-4.20 Beta Reasoning — which is better?

GPT-5.4 (by OpenAI) and Grok-4.20 Beta Reasoning (by xAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

On price, Grok-4.20 Beta Reasoning is roughly 1.9x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Grok-4.20 Beta Reasoning also accepts a larger context window (2,000,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose GPT-5.4 if…

  • you want predictable pricing at $2.50/M input and $15.00/M output

Choose Grok-4.20 Beta Reasoning if…

  • cost matters — it's about 1.9x cheaper per token
  • you process long inputs — it offers a 2,000,000 token context window
  • you want the most recent training data — it shipped Mar 2026
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Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

GPT-5.4 and Grok-4.20 Beta Reasoningdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Grok-4.20 Beta Reasoning costs less

For input processing, GPT-5.4 ($2.50/1M tokens) is 1.3x more expensive than Grok-4.20 Beta Reasoning ($2.00/1M tokens).

For output processing, GPT-5.4 ($15.00/1M tokens) is 2.5x more expensive than Grok-4.20 Beta Reasoning ($6.00/1M tokens).

In conclusion, GPT-5.4 is more expensive than Grok-4.20 Beta Reasoning.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Fri Jun 19 2026 • llm-stats.com
OpenAI
GPT-5.4
Input tokens$2.50
Output tokens$15.00
Best providerOpenAI
xAI
Grok-4.20 Beta Reasoning
Input tokens$2.00
Output tokens$6.00
Best providerxAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Grok-4.20 Beta Reasoning accepts 2,000,000 input tokens compared to GPT-5.4's 1,000,000 tokens. GPT-5.4 can generate longer responses up to 128,000 tokens, while Grok-4.20 Beta Reasoning is limited to 30,000 tokens.

OpenAI
GPT-5.4
Input1,000,000 tokens
Output128,000 tokens
xAI
Grok-4.20 Beta Reasoning
Input2,000,000 tokens
Output30,000 tokens
Fri Jun 19 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-5.4 and Grok-4.20 Beta Reasoning support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

GPT-5.4

Text
Images
Audio
Video

Grok-4.20 Beta Reasoning

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

GPT-5.4

Proprietary

Closed source

Grok-4.20 Beta Reasoning

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.4 was released on 2026-03-05, while Grok-4.20 Beta Reasoning was released on 2026-03-09.

Grok-4.20 Beta Reasoning is 0 month newer than GPT-5.4.

GPT-5.4

Mar 5, 2026

3 months ago

Grok-4.20 Beta Reasoning

Mar 9, 2026

3 months ago

4d newer

Knowledge Cutoff

When training data ends

Neither model specifies a knowledge cutoff date.

Unable to compare the recency of their training data.

No cutoff dates available

Provider Availability

GPT-5.4 is available from OpenAI. Grok-4.20 Beta Reasoning is available from xAI.

GPT-5.4

openai logo
OpenAI
Input Price:Input: $2.50/1MOutput Price:Output: $15.00/1M

Grok-4.20 Beta Reasoning

xai logo
xAI
Input Price:Input: $2.00/1MOutput Price:Output: $6.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

OpenAI

No standout differentiators in the data we have for this pair.

xAI
Larger context window (2,000,000 tokens)
Less expensive input tokens
Less expensive output tokens

Detailed Comparison

AI Model Comparison Table
Feature
OpenAI
GPT-5.4
xAI
Grok-4.20 Beta Reasoning

FAQ

Common questions about GPT-5.4 vs Grok-4.20 Beta Reasoning.

Which is better, GPT-5.4 or Grok-4.20 Beta Reasoning?

GPT-5.4 (OpenAI) and Grok-4.20 Beta Reasoning (xAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does GPT-5.4 compare to Grok-4.20 Beta Reasoning in benchmarks?

GPT-5.4 scores Tau2 Telecom: 98.9%, ARC-AGI: 93.7%, Graphwalks BFS <128k: 93.0%, GPQA: 92.8%, Graphwalks parents <128k: 89.8%. Grok-4.20 Beta Reasoning scores Finance Agent v2: 28.5%.

Is GPT-5.4 cheaper than Grok-4.20 Beta Reasoning?

Grok-4.20 Beta Reasoning is 1.3x cheaper for input tokens. GPT-5.4 costs $2.50/M input and $15.00/M output via openai. Grok-4.20 Beta Reasoning costs $2.00/M input and $6.00/M output via xai.

What are the context window sizes for GPT-5.4 and Grok-4.20 Beta Reasoning?

GPT-5.4 supports 1.0M tokens and Grok-4.20 Beta Reasoning supports 2.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-5.4 and Grok-4.20 Beta Reasoning?

Key differences include context window (1.0M vs 2.0M), input pricing ($2.50 vs $2.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-5.4 and Grok-4.20 Beta Reasoning?

GPT-5.4 is developed by OpenAI and Grok-4.20 Beta Reasoning is developed by xAI.

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