By the toolist.ai editors. Researched from public sources, not hands-on tested by toolist.ai. Updated November 3, 2026; prices checked November 3, 2026.

Gemini 4 Carbon vs Claude Opus 5.5

Verdict

Claude Opus 5.5 is the one you can buy today. Gemini 4 Carbon is limited to a subset of cyber defenders and trusted partners, and Google gives no date for everyone else. On published scores Carbon leads all five Artificial Analysis rows both have, narrowly on the Intelligence Index (60 against 59) and HLE-Diamond (69% against 68%), and more clearly on Terminal-Bench 4.0 (65% against 60%). Google says Carbon will launch at an introductory $2 and $10 per million tokens, half of Opus 5.5's $4 and $20, then rise to the same $4 and $20.

Verdict based on published prices, limits and benchmarks, not on our own tests.

Choose Gemini 4 Carbon if

  • You are among the cyber defenders or trusted partners Google is giving access to; nobody else can use it yet
  • You can wait and want the higher published scores: 65% against 59% on Terminal-Bench-Science and 58 against 48 on the Intelligence Index at medium effort
  • You can wait and accept the risk on price: Google announces an introductory $2 and $10 per million tokens but gives no launch date or end date, and Argon's introductory price ends November 30, 2026
  • You can wait and will send video or speech input; Claude Opus 5.5 takes text and images only

Choose Claude Opus 5.5 if

  • You need a model in production now, on the Claude API or through a cloud platform
  • You need a published output limit (128,000 tokens) and knowledge cutoff (June 2026); Google has published neither for Carbon
  • You run batch jobs, since the Batch API costs half

Price

These costs use the introductory price Google has announced for Gemini 4 Carbon. Nobody outside Google's first access groups can use Carbon yet, and the price rises to $4 and $20 per million tokens after an introductory period with no published end date.

Per million tokensGemini 4 CarbonClaude Opus 5.5
Input$2 source$4 source
Cached input$0.10 source$0.20 source
Output$10 source$20 source

Gemini 4 Carbon: Announced prices; Carbon is not on sale yet, and Google does not say whether its first groups pay. Google says Carbon will launch at the same introductory price as Gemini 4 Argon, with cached input 95% below the input price, then $4 per million input tokens and $20 per million output tokens. Argon's introductory period ends November 30, 2026; Google does not say whether Carbon's ends then too. Its Gemini API pricing page does not list Carbon yet, and Artificial Analysis lists $4 and $20. The 1,000,000-token context window is Artificial Analysis's rounded figure; Google has not published an exact limit.

Claude Opus 5.5: Cache writes cost $5 per million tokens (5-minute cache) or $8 (1-hour cache). The Batch API costs half. There is no long-context surcharge. Fast mode costs $8 in and $40 out.

Worked example: what a month costs

We priced three monthly workloads at the announced and listed rates above. The provider does not publish these figures.

WorkloadGemini 4 CarbonClaude Opus 5.5
Support chatbot
100,000 replies, each 3,000 input and 400 output tokens, no caching (300M in, 40M out)		 $1,000$2,000
Document Q&A
5,000 questions over the same 60,000-token document set (90% cache hits), 800 output tokens each (300M in, 4M out)		 $127$254
Coding agent
200 tasks, each 1.5 million input tokens (90% cache hits) and 50,000 output tokens (300M in, 10M out)		 $187$374

Price your own workload

ModelCost a month
Gemini 4 Carbon $150
Claude Opus 5.5 $300

Announced and listed prices, no batch or priority discounts. Cached input is billed at the cache-read price; cache-write charges are not included. Reasoning models bill their thinking as output tokens.

Limits and release dates

Gemini 4 CarbonClaude Opus 5.5
ReleasedAnnounced October 28, 2026 sourceSeptember 22, 2026 source
Context window1,000,000 tokens source1,000,000 tokens source
Maximum outputnot published128,000 tokens source
Knowledge cutoffnot publishedJune 2026 source
Input and outputText, images, speech and video in; text out sourceText and images in; text out source
API model nameNot published yetclaude-opus-5-5

Benchmarks

Scores as published by the provider or measured by Artificial Analysis; higher is better. A dash means no score was published.

BenchmarkGemini 4 CarbonClaude Opus 5.5
Artificial Analysis Intelligence Index 60.0 (high thinking, the highest level Artificial Analysis tests) source59.0 (max effort) source
Intelligence Index at everyday effort 58.0 (medium thinking; Google has not published a default) source48.0 (medium effort, the API default) source
Terminal-Bench 4.0 65.0% (high thinking) source60.0% (max effort) source
HLE-Diamond 69.0% (high thinking) source68.0% (max effort) source
Terminal-Bench-Science 0.1 65.0% (high thinking) source59.0% (max effort) source
Output speed 88.7 tokens/s (high thinking, Artificial Analysis) source77.9 tokens/s (medium effort, Artificial Analysis) source

Benchmark and speed data from Artificial Analysis where linked.

Read more

Sources