Model Comparison

Seed 2.0 Pro vs GPT-5.5Which is better in 2026?

GPT-5.5 significantly outperforms across most benchmarks. Seed 2.0 Pro is 10.0x cheaper per token.

Verdict: Seed 2.0 Pro vs GPT-5.5 — which is better?

Seed 2.0 Pro (by ByteDance) and GPT-5.5 (by OpenAI) 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.

Seed 2.0 Pro outperforms in 0 benchmarks, while GPT-5.5 is better at 2 benchmarks (BrowseComp, GPQA). GPT-5.5 significantly outperforms across most benchmarks.

On price, Seed 2.0 Pro is roughly 10.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5.5 also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Seed 2.0 Pro if…

  • cost matters — it's about 10.0x cheaper per token

Choose GPT-5.5 if…

  • you want the strongest raw capability — it leads on 2 of 2 shared benchmarks
  • you process long inputs — it offers a 1,050,000 token context window
  • you want the most recent training data — it shipped Apr 2026

Performance Benchmarks

Comparative analysis across standard metrics

2 benchmarks

Seed 2.0 Pro outperforms in 0 benchmarks, while GPT-5.5 is better at 2 benchmarks (BrowseComp, GPQA).

GPT-5.5 significantly outperforms across most benchmarks.

Sun Jul 05 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Seed 2.0 Pro costs less

For input processing, Seed 2.0 Pro ($0.50/1M tokens) is 10.0x cheaper than GPT-5.5 ($5.00/1M tokens).

For output processing, Seed 2.0 Pro ($3.00/1M tokens) is 10.0x cheaper than GPT-5.5 ($30.00/1M tokens).

In conclusion, GPT-5.5 is more expensive than Seed 2.0 Pro.*

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

Lowest available price from all providers
Sun Jul 05 2026 • llm-stats.com
ByteDance
Seed 2.0 Pro
Input tokens$0.50
Output tokens$3.00
Best providerDeepinfra
OpenAI
GPT-5.5
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5.5 accepts 1,050,000 input tokens compared to Seed 2.0 Pro's 256,000 tokens. GPT-5.5 can generate longer responses up to 128,000 tokens, while Seed 2.0 Pro is limited to 65,536 tokens.

ByteDance
Seed 2.0 Pro
Input256,000 tokens
Output65,536 tokens
OpenAI
GPT-5.5
Input1,050,000 tokens
Output128,000 tokens
Sun Jul 05 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Seed 2.0 Pro and GPT-5.5 support multimodal inputs.

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

Seed 2.0 Pro

Text
Images
Audio
Video

GPT-5.5

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.

Seed 2.0 Pro

Proprietary

Closed source

GPT-5.5

Proprietary

Closed source

Release Timeline

When each model was launched

Seed 2.0 Pro was released on 2026-02-14, while GPT-5.5 was released on 2026-04-23.

GPT-5.5 is 2 months newer than Seed 2.0 Pro.

Seed 2.0 Pro

Feb 14, 2026

4 months ago

GPT-5.5

Apr 23, 2026

2 months ago

2mo newer

Knowledge Cutoff

When training data ends

Seed 2.0 Pro has a knowledge cutoff of 2024-01-01, while GPT-5.5 has a cutoff of 2025-12-01.

GPT-5.5 has more recent training data (up to 2025-12-01), making it potentially better informed about events through that date compared to Seed 2.0 Pro (2024-01-01).

Seed 2.0 Pro

Jan 2024

GPT-5.5

Dec 2025

1.9 yr newer

Provider Availability

Seed 2.0 Pro is available from DeepInfra. GPT-5.5 is available from OpenAI.

Seed 2.0 Pro

deepinfra logo
Deepinfra
Input Price:Input: $0.50/1MOutput Price:Output: $3.00/1M

GPT-5.5

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

ByteDance
Less expensive input tokens
Less expensive output tokens
OpenAI
Larger context window (1,050,000 tokens)
Higher BrowseComp score (84.4% vs 77.3%)
Higher GPQA score (93.6% vs 88.9%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Seed 2.0 Pro and GPT-5.5 side-by-side, then vote on the output you prefer.

Seed 2.0 Pro
✓ Preferred
GPT-5.5
Open in Playground
AI Model Comparison Table
Feature
ByteDance
Seed 2.0 Pro
OpenAI
GPT-5.5

FAQ

Common questions about Seed 2.0 Pro vs GPT-5.5.

Which is better, Seed 2.0 Pro or GPT-5.5?

GPT-5.5 significantly outperforms across most benchmarks. Seed 2.0 Pro is made by ByteDance and GPT-5.5 is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Seed 2.0 Pro compare to GPT-5.5 in benchmarks?

Seed 2.0 Pro scores AIME 2025: 98.3%, AIME 2026: 94.2%, GPQA: 88.9%, LiveCodeBench v6: 87.8%, BrowseComp: 77.3%. GPT-5.5 scores Tau2 Telecom: 98.0%, ARC-AGI: 95.0%, GPQA: 93.6%, ARC-AGI v2: 85.0%, GDPval-MM: 84.9%.

Is Seed 2.0 Pro cheaper than GPT-5.5?

Seed 2.0 Pro is 10.0x cheaper for input tokens. Seed 2.0 Pro costs $0.50/M input and $3.00/M output via deepinfra. GPT-5.5 costs $5.00/M input and $30.00/M output via openai.

What are the context window sizes for Seed 2.0 Pro and GPT-5.5?

Seed 2.0 Pro supports 256K tokens and GPT-5.5 supports 1.1M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Seed 2.0 Pro and GPT-5.5?

Key differences include context window (256K vs 1.1M), input pricing ($0.50 vs $5.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Seed 2.0 Pro and GPT-5.5?

Seed 2.0 Pro is developed by ByteDance and GPT-5.5 is developed by OpenAI.

Related comparisons