Router One

Grok 4.5 vs GPT-5.5

Grok 4.5 and GPT-5.5 compared on current per-token rates, context window, and capabilities — both callable through one OpenAI-compatible endpoint with per-request cost traces.

Grok 4.5 vs GPT-5.5: rates, context window, and capabilities

SpecGrok 4.5GPT-5.5
Input / 1M tokens$0.80$0.50
Output / 1M tokens$2.40$2.25
Cached input / 1M tokens$0.20$0.13
Context window500k1.1M
CapabilitiesChat, Streaming, Tool calling, VisionChat, Streaming, Tool calling, Vision
Detail pageGrok 4.5GPT-5.5

What does 1M tokens cost on Grok 4.5 vs GPT-5.5?

For a workload of 1M input plus 1M output tokens at current rates: Grok 4.5 comes to $3.20, GPT-5.5 comes to $2.75 — GPT-5.5 is about 14% cheaper on this mix. Real workloads skew heavily toward input tokens, so weigh the input rate by your own ratio; prompt-cache hits bill at the cached-input rate where supported.

Switch between Grok 4.5 and GPT-5.5 without changing code

Both models are behind the same OpenAI-compatible endpoint, so an A/B test is a one-string change — same key, same code, and every request traced with tokens, cost, and latency in the dashboard:

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": "grok-4.5", "messages": [{"role": "user", "content": "Hello"}]}'

# Same request, other model — change one string:
#   "model": "openai/gpt-5.5"

FAQ

Is Grok 4.5 cheaper than GPT-5.5?

At current posted rates, GPT-5.5 is the cheaper of the two (input $0.80 vs $0.50, output $2.40 vs $2.25 per 1M tokens). Rates change; the /models page is the live source of truth.

Can I switch between Grok 4.5 and GPT-5.5 without changing code?

Yes. Both are served through the same OpenAI-compatible endpoint, so switching is changing the model string in the request — the key, base URL, and request shape stay identical.

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.

More comparisons

All model comparisons