Model Comparison

GPT-5.4 vs Seed 2.1 ProWhich is better in 2026?

Seed 2.1 Pro shows notably better performance in the majority of benchmarks.

Verdict: GPT-5.4 vs Seed 2.1 Pro — which is better?

GPT-5.4 (by OpenAI) and Seed 2.1 Pro (by ByteDance) 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.

GPT-5.4 outperforms in 2 benchmarks (SWE-Bench Pro, Toolathlon), while Seed 2.1 Pro is better at 4 benchmarks (BrowseComp, Humanity's Last Exam, MCP Atlas, MMMU-Pro). Seed 2.1 Pro shows notably better performance in the majority of benchmarks.

Choose GPT-5.4 if…

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

Choose Seed 2.1 Pro if…

  • you want the strongest raw capability — it leads on 4 of 6 shared benchmarks
  • you want the most recent training data — it shipped Jun 2026
Want to compare interactively?Try the playground

Performance Benchmarks

Comparative analysis across standard metrics

6 benchmarks

GPT-5.4 outperforms in 2 benchmarks (SWE-Bench Pro, Toolathlon), while Seed 2.1 Pro is better at 4 benchmarks (BrowseComp, Humanity's Last Exam, MCP Atlas, MMMU-Pro).

Seed 2.1 Pro shows notably better performance in the majority of benchmarks.

Thu Jun 25 2026 • llm-stats.com

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only GPT-5.4 specifies input context (1,000,000 tokens). Only GPT-5.4 specifies output context (128,000 tokens).

OpenAI
GPT-5.4
Input1,000,000 tokens
Output128,000 tokens
ByteDance
Seed 2.1 Pro
Input- tokens
Output- tokens
Thu Jun 25 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both GPT-5.4 and Seed 2.1 Pro support multimodal inputs.

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

GPT-5.4

Text
Images
Audio
Video

Seed 2.1 Pro

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

Seed 2.1 Pro

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-5.4 was released on 2026-03-05, while Seed 2.1 Pro was released on 2026-06-24.

Seed 2.1 Pro is 4 months newer than GPT-5.4.

GPT-5.4

Mar 5, 2026

3 months ago

Seed 2.1 Pro

Jun 24, 2026

1 days ago

3mo 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

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

OpenAI
Larger context window (1,000,000 tokens)
Higher SWE-Bench Pro score (57.7% vs 57.5%)
Higher Toolathlon score (54.6% vs 50.6%)
ByteDance
Higher BrowseComp score (86.2% vs 82.7%)
Higher Humanity's Last Exam score (55.7% vs 39.8%)
Higher MCP Atlas score (83.8% vs 67.2%)
Higher MMMU-Pro score (82.7% vs 81.2%)

Detailed Comparison

AI Model Comparison Table
Feature
OpenAI
GPT-5.4
ByteDance
Seed 2.1 Pro

FAQ

Common questions about GPT-5.4 vs Seed 2.1 Pro.

Which is better, GPT-5.4 or Seed 2.1 Pro?

Seed 2.1 Pro shows notably better performance in the majority of benchmarks. GPT-5.4 is made by OpenAI and Seed 2.1 Pro is made by ByteDance. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does GPT-5.4 compare to Seed 2.1 Pro 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%. Seed 2.1 Pro scores CharXiv-D: 95.5%, MathVision: 94.5%, MathVista: 90.7%, MathVerse: 89.7%, Video-MME: 89.2%.

What are the context window sizes for GPT-5.4 and Seed 2.1 Pro?

GPT-5.4 supports 1.0M tokens and Seed 2.1 Pro supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

Who makes GPT-5.4 and Seed 2.1 Pro?

GPT-5.4 is developed by OpenAI and Seed 2.1 Pro is developed by ByteDance.

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