GPT 5.5 vs Kimi K2.8 Preview

Specification table

Both models are served through the same OpenAI-compatible Tokenator endpoint — switching between them means changing the model field in your request. The table below lists only the attributes Tokenator takes from its own routing configuration, with no editorial guesswork.

Quality on available benchmarks

Values come from the Artificial Analysis data loaded into the Tokenator catalog for these models. A dash means no data is loaded for that index.

Differences in purpose

GPT 5.5

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks.

Kimi K2.8 Preview

Kimi K2.8 Preview is a multimodal model by Moonshot AI designed for coding, complex reasoning, and autonomous agentic tasks. It supports a context window of up to 1 million tokens, image and video input, and long-running multi-step workflows with tool use. According to Moonshot AI, K2.8 Preview delivers performance close to the flagship Kimi K3 while using compute more efficiently.

Both IDs work in any tool that supports a custom base URL — see the integrations list.

Token usage

Tokenator deducts (input + output) × model multiplier from the key limit. GPT 5.5 has a multiplier of 1.8×, Kimi K2.8 Preview — 1.4×. A range means several upstream providers serve the model at different costs, so the final coefficient depends on which one handled the request.

See the API documentation for details on counting.

How to switch between the models

curl https://api.tokenator.top/v1/chat/completions \
  -H "Authorization: Bearer sk-your-tokenator-key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5.5",
    "messages": [{"role": "user", "content": "Hello"}]
  }'

curl https://api.tokenator.top/v1/chat/completions \
  -H "Authorization: Bearer sk-your-tokenator-key" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "kimi-k2.8-preview",
    "messages": [{"role": "user", "content": "Hello"}]
  }'

FAQ

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