Seed 1.8 vs GPT-5
Benchmark Performance
Available Benchmarks
Technical Differences
Side-by-Side Facts
| Field | Seed 1.8 | GPT-5 |
|---|---|---|
| Developer | ByteDance Seed | OpenAI |
| Family | Seed 1 8 | Gpt 5 |
| Model | Seed 1.8 | GPT-5 |
| Version | Seed 1.8 | GPT-5 |
| Lifecycle | active | active |
| Released | Unknown | 2025-08-07 |
| Knowledge cutoff | Unknown | 2024-09-30 |
| Input modalities | Text, Image | Text, Image |
| Output modalities | Text | Text |
| Context window | Unknown | 400,000 |
| 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 | Unknown | Openai (Standard), Openrouter (Standard) |
| Capabilities | chat, generation, reasoning, tools | chat, generation, reasoning, structured_outputs, tools |
11 comparable fields · 5 material differences · Pair passes the primary-source comparison gate
Seed 1.8 Capabilities
GPT-5 Capabilities
Internal Comparison Graph
Related Comparisons
| A | Pair | B | Context |
|---|---|---|---|
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GPT-5OpenAI | vs | GPT-5 MiniOpenAI | family variantsimage, text |
Seed 1.8ByteDance Seed | vs | Seed 2.0 MiniByteDance Seed | family variantsimage, text |
Seed 1.8ByteDance Seed | vs | Seed 2.1 ProByteDance Seed | family variantsimage, text |
Seed 1.8ByteDance Seed | vs | Seed 2.1 EvolvingByteDance Seed | family variantsimage, text |
Seed 1.8ByteDance Seed | vs | Seed 2.1 TurboByteDance Seed | family variantsimage, text |
GPT-5OpenAI | vs | Grok 4.5xAI | cross-developer peersimage, text |
Claude Opus 4.5Anthropic | vs | GPT-5OpenAI | cross-developer peersimage, text |
GPT-4oOpenAI | vs | GPT-5OpenAI | family variantsimage, text |
GPT-4o MiniOpenAI | vs | GPT-5OpenAI | family variantsimage, text |
Seed 2.1 EvolvingByteDance Seed | vs | GPT-5OpenAI | cross-developer peersimage, text |
Seed 2.1 TurboByteDance Seed | vs | GPT-5OpenAI | cross-developer peersimage, text |
Primary Evidence
Sources and Freshness
Questions
Seed 1.8 vs GPT-5 FAQs
Is Seed 1.8 or GPT-5 better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Seed 1.8 and GPT-5, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, Seed 1.8 or GPT-5?+
Only GPT-5 has a directly sourced input price: $0.625 per million tokens. Only GPT-5 has a directly sourced output price: $5.00 per million tokens.
Which has a larger context window, Seed 1.8 or GPT-5?+
Neither model has a larger sourced context window in this comparison. Seed 1.8 is — and GPT-5 is 400,000.
Which performs better in benchmarks, Seed 1.8 or GPT-5?+
There is no overall benchmark winner: At least two independently verified, protocol-matched benchmarks are required for an overall winner.
Can Seed 1.8 or GPT-5 be self-hosted?+
Both models have the same recorded self-hosting status: unsupported. Seed 1.8 is not marked open weight; GPT-5 is not marked open weight.
Can Seed 1.8 and GPT-5 understand images?+
Seed 1.8 is documented with image input; GPT-5 is documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, Seed 1.8 or GPT-5?+
Neither has a larger sourced maximum output. Seed 1.8 is — and GPT-5 is 128,000.
Do Seed 1.8 and GPT-5 support reasoning and tool use?+
Seed 1.8: reasoning, tool calling, and image input. GPT-5: reasoning, tool calling, and image input. Feature support does not establish relative quality.
Which is available from more inference providers, Seed 1.8 or GPT-5?+
Seed 1.8 has 0 sourced provider routes; GPT-5 has 2, so GPT-5 has broader tracked availability.
Which offers better value, Seed 1.8 or GPT-5?+
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.