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GPT-6 Sol vs GPT-5.6 Sol

GPT-6 Sol is the lower-priced of the two on Router One at base-tier rates (GPT-6 Sol and GPT-5.6 Sol: request input ≤ 272,000 tokens) — about 47% less on a 1M-input + 1M-output mix. Both carry a 1.05M context window. Both answer on /v1/chat/completions and /v1/responses (Codex CLI).

GPT-6 Sol and GPT-5.6 Sol compared on current per-token rates, context window, and capabilities — both callable through one OpenAI-compatible endpoint that logs each request it forwards.

GPT-6 Sol vs GPT-5.6 Sol: rates, context window, and capabilities

SpecGPT-6 SolGPT-5.6 Sol
Input / 1M tokens$0.40$0.50
Output / 1M tokens$2.00$4.00
Cached input / 1M tokens$0.04$0.25
Context window1.05M1.05M
CapabilitiesChat, Streaming, Tool calling, VisionChat, Streaming, Tool calling, Vision
Subscription plansPremium models — Pro, Max, UltraPremium models — Pro, Max, Ultra
Detail pageGPT-6 SolGPT-5.6 Sol

GPT-6 Sol: request input ≤ 272,000 tokens: Input $0.40 / 1M tokens, Output $2.00 / 1M tokens, Cache write $0.50 / 1M tokens, Cached input $0.04 / 1M tokens; request input > 272,000 tokens: Input $0.80 / 1M tokens, Output $3.00 / 1M tokens, Cache write $1.00 / 1M tokens, Cached input $0.08 / 1M tokens. The total input tokens in each request select the tier; its rates apply to the whole request, not only tokens above the threshold.

GPT-5.6 Sol: request input ≤ 272,000 tokens: Input $0.50 / 1M tokens, Output $4.00 / 1M tokens, Cache write $0.50 / 1M tokens, Cached input $0.25 / 1M tokens; request input > 272,000 tokens: Input $1.00 / 1M tokens, Output $4.50 / 1M tokens, Cache write $6.25 / 1M tokens, Cached input $0.50 / 1M tokens. The total input tokens in each request select the tier; its rates apply to the whole request, not only tokens above the threshold.

What does 1M tokens cost on GPT-6 Sol vs GPT-5.6 Sol?

Base-tier rates: For a workload of 1M input plus 1M output tokens at current rates: GPT-6 Sol comes to $2.40, GPT-5.6 Sol comes to $4.50 — GPT-6 Sol is about 47% cheaper on this mix. Real workloads skew heavily toward input tokens, so weigh the input rate by your own ratio; the cached-input row above is the posted catalog rate for that model.

Switch between GPT-6 Sol and GPT-5.6 Sol

The API key, base URL and endpoints stay the same, but GPT-5.6 Sol code may still need changes before it runs on GPT-6 Sol. Per OpenAI's GPT-6 Sol model page and GPT-6 guide (checked 2026-10-01), GPT-6 Sol supports function calling on Chat Completions only with reasoning_effort set to none (the default is medium), OpenAI points to the Responses API for tools, and at any effort other than none GPT-6 Sol takes no temperature, top_p or logprobs settings. So GPT-5.6 Sol code that sends tools on /v1/chat/completions at another effort should move to /v1/responses.

compare.sh
curl https://api.router.one/v1/chat/completions \
  -H "Authorization: Bearer sk-your-router-one-key" \
  -H "Content-Type: application/json" \
  -d '{"model": "openai/gpt-6-sol", "messages": [{"role": "user", "content": "Hello"}]}'

# Same request, other model — change one string:
#   "model": "openai/gpt-5.6-sol"

FAQ

Is GPT-6 Sol cheaper than GPT-5.6 Sol?

Compared at base-tier rates (GPT-6 Sol and GPT-5.6 Sol: request input ≤ 272,000 tokens). Input: GPT-6 Sol $0.40 vs GPT-5.6 Sol $0.50 / 1M tokens; GPT-6 Sol has the lower rate. Output: GPT-6 Sol $2.00 vs GPT-5.6 Sol $4.00 / 1M tokens; GPT-6 Sol has the lower rate. Total cost depends on the workload's input, output and cache usage. GPT-6 Sol: request input ≤ 272,000 tokens: Input $0.40 / 1M tokens, Output $2.00 / 1M tokens, Cache write $0.50 / 1M tokens, Cached input $0.04 / 1M tokens; request input > 272,000 tokens: Input $0.80 / 1M tokens, Output $3.00 / 1M tokens, Cache write $1.00 / 1M tokens, Cached input $0.08 / 1M tokens. The total input tokens in each request select the tier; its rates apply to the whole request, not only tokens above the threshold. GPT-5.6 Sol: request input ≤ 272,000 tokens: Input $0.50 / 1M tokens, Output $4.00 / 1M tokens, Cache write $0.50 / 1M tokens, Cached input $0.25 / 1M tokens; request input > 272,000 tokens: Input $1.00 / 1M tokens, Output $4.50 / 1M tokens, Cache write $6.25 / 1M tokens, Cached input $0.50 / 1M tokens. The total input tokens in each request select the tier; its rates apply to the whole request, not only tokens above the threshold. Rates change; the /models page is the live source of truth.

Is GPT-6 Sol or GPT-5.6 Sol included in a Router One subscription?

GPT-6 Sol and GPT-5.6 Sol both count against the Premium models allowance on Pro, Max and Ultra: Pro 300, Max 1,000 and Ultra 5,000 requests per 30-day cycle, one pool shared by every model in that tier. Requests to GPT-6 Sol or GPT-5.6 Sol above the model's long-context threshold count as more than one quota request. Requests beyond a plan's allowance bill the wallet per token.

Can I switch between GPT-6 Sol and GPT-5.6 Sol without changing code?

The API key, base URL and endpoints stay the same, but GPT-5.6 Sol code may still need changes before it runs on GPT-6 Sol. Per OpenAI's GPT-6 Sol model page and GPT-6 guide (checked 2026-10-01), GPT-6 Sol supports function calling on Chat Completions only with reasoning_effort set to none (the default is medium), OpenAI points to the Responses API for tools, and at any effort other than none GPT-6 Sol takes no temperature, top_p or logprobs settings. So GPT-5.6 Sol code that sends tools on /v1/chat/completions at another effort should move to /v1/responses.

Where do these numbers come from?

Specs and prices on this page render from the live Router One catalog — the same data as the /models page — and refresh with it. Pricing methodology is documented on /pricing-methodology. Rates on this page were read from the live catalog on 2026-11-11 (UTC) and refresh within the hour.

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