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GPT-6 Astra vs Seed 1.8

GPT-6 Astra leads the LLM Stats Score 60.3 to 34.2. Seed 1.8 is 29.1x cheaper per token.

OpenAI · ByteDance · Updated for 2026

Which is better?

GPT-6 Astra leads the overall LLM Stats Score 60.3 to 34.2, ranking #1 overall.

In the 3 individual benchmarks reported for both models, GPT-6 Astra wins 3; this is a narrower head-to-head signal than the composite indexes.

On price, Seed 1.8 is roughly 29.1x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-6 Astra also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose GPT-6 Astra

  • overall performance matters — it scores 60.3 and ranks #1 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 3 of 3 exact shared results
  • you process long inputs — it offers a 1,050,000 token context window
  • you want the most recent training data — it shipped Sep 2026

Choose Seed 1.8

  • cost matters — it's about 29.1x cheaper per token

At a glance

The differences that matter most.

Core performance indexes
60.3
#1
34.2
#91
58.2
#1
33.5
#93
48.5
#1
19.8
#99
46.4
#1
14.9
#86
Cost, coverage & limits
Benchmark wins
3 of 3
0 of 3
Input price
$10.00 / M
$0.25 / M
Output price
$50.00 / M
$2.00 / M
Context window
1,050,000
256,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

4 shared
Index
GPT-6 Astra
Seed 1.8
35.9#42
32.5#57
41.7#1
24.1#51
36.1#1
6.6#142
39.0#2
27.4#38
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

22 reported for GPT-6 Astra · 57 for Seed 1.8

3 shared

GPT-6 Astra outperforms in 3 benchmarks (ARC-AGI, BrowseComp, Humanity's Last Exam (with tools, text-only)), while Seed 1.8 is better at 0 benchmarks.

GPT-6 Astra significantly outperforms across most benchmarks.

Wed Sep 09 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Seed 1.8 costs less

For input processing, GPT-6 Astra ($10.00/1M tokens) is 40.0x more expensive than Seed 1.8 ($0.25/1M tokens).

For output processing, GPT-6 Astra ($50.00/1M tokens) is 25.0x more expensive than Seed 1.8 ($2.00/1M tokens).

In conclusion, GPT-6 Astra is more expensive than Seed 1.8.*

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

Lowest available price from all providers
Wed Sep 09 2026 • llm-stats.com
OpenAI
GPT-6 Astra
Input tokens$10.00
Output tokens$50.00
Best providerOpenAI
ByteDance
Seed 1.8
Input tokens$0.25
Output tokens$2.00
Best providerDeepinfra
Notice missing or incorrect data?Start an Issue

Context Window

Maximum input and output token capacity

GPT-6 Astra accepts 1,050,000 input tokens compared to Seed 1.8's 256,000 tokens. Seed 1.8 can generate longer responses up to 256,000 tokens, while GPT-6 Astra is limited to 128,000 tokens.

OpenAI
GPT-6 Astra
Input1,050,000 tokens
Output128,000 tokens
ByteDance
Seed 1.8
Input256,000 tokens
Output256,000 tokens
Wed Sep 09 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both GPT-6 Astra and Seed 1.8 support multimodal inputs.

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

GPT-6 Astra

Text
Images
Audio
Video

Seed 1.8

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-6 Astra

Proprietary

Closed source

Seed 1.8

Proprietary

Closed source

Release Timeline

When each model was launched

GPT-6 Astra was released on 2026-09-04, while Seed 1.8 was released on 2026-02-17.

GPT-6 Astra is 7 months newer than Seed 1.8.

GPT-6 Astra

Sep 4, 2026

4 days ago

6mo newer
Seed 1.8

Feb 17, 2026

6 months ago

Knowledge Cutoff

When training data ends

GPT-6 Astra has a documented knowledge cutoff of 2026-04-30, while Seed 1.8's cutoff date is not specified.

We can confirm GPT-6 Astra's training data extends to 2026-04-30, but cannot make a direct comparison without Seed 1.8's cutoff date.

GPT-6 Astra

Apr 2026

Seed 1.8

Provider Availability

GPT-6 Astra is available from OpenAI. Seed 1.8 is available from DeepInfra.

GPT-6 Astra

openai logo
OpenAI
Input Price:Input: $10.00/1MOutput Price:Output: $50.00/1M

Seed 1.8

deepinfra logo
Deepinfra
Input Price:Input: $0.25/1MOutput Price:Output: $2.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against GPT-6 Astra and Seed 1.8 side-by-side, then vote on the output you prefer.

GPT-6 Astra
✓ Preferred
Seed 1.8
Open in Playground

FAQ

Common questions about GPT-6 Astra vs Seed 1.8.

Which is better, GPT-6 Astra or Seed 1.8?

GPT-6 Astra leads the LLM Stats Score 60.3 to 34.2. GPT-6 Astra is made by OpenAI and Seed 1.8 is made by ByteDance. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does GPT-6 Astra compare to Seed 1.8 in benchmarks?

GPT-6 Astra scores ExploitBench: 100.0%, ARC-AGI-3: 99.9%, ARC-AGI: 98.5%, FrontierMath Tier 4 (v2): 97.6%, GPQA: 96.0%. Seed 1.8 scores CountBench: 96.3%, AIME 2025: 94.3%, VLMsAreBlind: 93.0%, MMLU: 92.3%, AI2D: 89.1%.

Is GPT-6 Astra cheaper than Seed 1.8?

Seed 1.8 is 40.0x cheaper for input tokens. GPT-6 Astra costs $10.00/M input and $50.00/M output via openai. Seed 1.8 costs $0.25/M input and $2.00/M output via deepinfra.

What are the context window sizes for GPT-6 Astra and Seed 1.8?

GPT-6 Astra supports 1.1M tokens and Seed 1.8 supports 256K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between GPT-6 Astra and Seed 1.8?

Key differences include LLM Stats Score (60.3 vs 34.2), context window (1.1M vs 256K), input pricing ($10.00 vs $0.25/M). See the full comparison above for benchmark-by-benchmark results.

Who makes GPT-6 Astra and Seed 1.8?

GPT-6 Astra is developed by OpenAI and Seed 1.8 is developed by ByteDance.