Claude Opus 4.5 vs Seed 1.8
Model Markets Rankings
Intelligence, Cost, and Efficiency
| Ranking | Claude Opus 4.5 | Seed 1.8 |
|---|---|---|
| CostLower is better · Published-token output estimate | #34 of 36$0.380 per LiveBench case | UnrankedNot in the 36-model eligible cohort |
Ranks come from the current complete eligible cohorts. Green highlights appear only when both models are ranked in the same metric. Missing required inputs remain unranked, and the three dimensions are not collapsed into an overall winner.
Benchmark Performance
Available Benchmarks
Technical Differences
Side-by-Side Facts
| Field | Claude Opus 4.5 | Seed 1.8 |
|---|---|---|
| Developer | Anthropic | ByteDance Seed |
| Family | Claude 4 | Seed 1 8 |
| Model | Claude Opus 4.5 | Seed 1.8 |
| Version | Claude Opus 4.5 | Seed 1.8 |
| Lifecycle | active | active |
| Released | 2025-11-24 | Unknown |
| Knowledge cutoff | 2025-05-01 | Unknown |
| Input modalities | Text, Image | Text, Image |
| Output modalities | Text | Text |
| Context window | 200K | Unknown |
| Total parameters | Unknown | Unknown |
| Active parameters | Unknown | Unknown |
| License | Unknown | Unknown |
| Open weights | No | No |
| API available | Yes | Yes |
| Self-hostable | No | No |
| Provider access | Anthropic (Standard) | Unknown |
| Capabilities | chat, generation, reasoning, structured_outputs, tools | chat, generation, reasoning, tools |
11 comparable fields · 5 material differences · Pair passes the primary-source comparison gate
Claude Opus 4.5 Capabilities
Seed 1.8 Capabilities
Internal Comparison Graph
Related Comparisons
| A | Pair | B | Context |
|---|---|---|---|
Claude Opus 4.5Anthropic | vs |  GPT-6 AstraOpenAI | cross-developer peersimage, text |
Claude Fable 5.1Anthropic | vs | Claude Opus 4.5Anthropic | family variantsimage, text |
Claude Opus 4.5Anthropic | vs |  Gemini 3.1 ProGoogle DeepMind | cross-developer peerstext |
Claude Opus 4.5Anthropic | vs |  DeepSeek-V4-ProDeepSeek | cross-developer peerstext |
Claude Opus 4.5Anthropic | vs | Grok 4.6xAI | cross-developer peersimage, text |
Claude Opus 4.5Anthropic | vs |  Qwen3.8-MaxQwen | cross-developer peersimage, text |
Claude Opus 4.5Anthropic | vs |  Kimi-K3Moonshot AI | cross-developer peersimage, text |
 MiniMax-M3MiniMax | vs | Claude Opus 4.5Anthropic | cross-developer peersimage, text |
Claude Opus 4.5Anthropic | vs |  GLM-5.3Z.ai | cross-developer peerstext |
Claude Opus 4.5Anthropic | vs |  Hy4 previewTencent | cross-developer peerstext |
Claude Opus 4.5Anthropic | vs | Seed 2.1 ProByteDance Seed | cross-developer peersimage, text |
Claude Opus 4.5Anthropic | vs |  Mistral Large 3Mistral AI | cross-developer peersimage, text |
Primary Evidence
Sources and Freshness
Questions
Claude Opus 4.5 vs Seed 1.8 FAQs
Is Claude Opus 4.5 or Seed 1.8 better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Opus 4.5 and Seed 1.8, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Claude Opus 4.5 or Seed 1.8?+
Only Claude Opus 4.5 has a directly sourced input price: $5.00 per million tokens. Only Claude Opus 4.5 has a directly sourced output price: $25.00 per million tokens.
Which has a larger context window, Claude Opus 4.5 or Seed 1.8?+
Neither model has a larger sourced context window in this comparison. Claude Opus 4.5 is 200K and Seed 1.8 is —.
Which performs better in benchmarks, Claude Opus 4.5 or Seed 1.8?+
There is no overall benchmark winner: At least two independently verified, protocol-matched benchmarks are required for an overall winner.
Can Claude Opus 4.5 or Seed 1.8 be self-hosted?+
Both models have the same recorded self-hosting status: unsupported. Claude Opus 4.5 is not marked open weight; Seed 1.8 is not marked open weight.
Can Claude Opus 4.5 and Seed 1.8 understand images?+
Claude Opus 4.5 is documented with image input; Seed 1.8 is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Claude Opus 4.5 or Seed 1.8?+
Neither has a larger sourced maximum output. Claude Opus 4.5 is 64K and Seed 1.8 is —.
Do Claude Opus 4.5 and Seed 1.8 support reasoning and tool use?+
Claude Opus 4.5: reasoning, tool calling, and image input. Seed 1.8: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, Claude Opus 4.5 or Seed 1.8?+
Claude Opus 4.5 has 1 sourced provider route; Seed 1.8 has 0, so Claude Opus 4.5 has broader tracked availability.
Which offers better value, Claude Opus 4.5 or Seed 1.8?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.