Google announced Gemini 4 Carbon on October 28, 2026, describing it as the company’s strongest frontier model, and said it will reach users through a staged rollout that begins with a subset of cyber defenders rather than a broad release.
In the announcement, Koray Kavukcuoglu, SVP of Google DeepMind and Chief AI Architect at Google, characterized Carbon as the company’s strongest model, with state-of-the-art cybersecurity and long-horizon capabilities. Carbon succeeds Gemini 4 Argon, which Google launched two weeks before the Carbon announcement. Google said the new model illustrates the pace at which it is pushing the frontier forward while strengthening its safeguards in tandem.
Google said it is taking a deliberate approach to deployment and is actively engaged in the U.S. government’s voluntary process for pre-release model testing. Starting the week of the announcement, the company will make Carbon available to a subset of cyber defenders, then gradually phase access to additional trusted partners through its Fairwind Program. Google said it is continuing to gather feedback and iterate on guardrails before making the model available to developers, businesses, and consumers through its product surfaces, adding that it intends to do so as soon as possible.
Long-Horizon Coding and General Benchmarks
Google said Carbon is designed for harder, long-horizon engineering problems and built for sustained agentic workflows, and that internal teams have seen the model run for days and persist through dead ends on complex, multi-step tasks such as root-causing and patching subtle bugs across large codebases and low-level systems.
According to Google, Carbon ranks first on the recently updated version 5.0 of the Artificial Analysis Intelligence Index with a score of 59. The company reported that Carbon gained 89 elo points to reach fourth place with a score of 1768 on WebDev Arena, citing improved quality of web development output and artifacts. Google said it focused its improvements on coding, agentic, and scientific tasks, as well as full-stack web development and multimodal understanding, building on user feedback.
Cybersecurity Defense Performance
Google reported state-of-the-art results across the cybersecurity defense lifecycle of vulnerability detection, validation, and remediation, and said the external evaluations were run without guardrails. On SEC-bench Pro, which measures the autonomous discovery of complex flaws in real-world software, Google reported 88.2%. On ExploitGym, a benchmark used to validate whether identified vulnerabilities are exploitable, Google reported a new state-of-the-art score of 54.8%. On Collinear’s CWE-bench, which tests patching vulnerabilities at the root cause, Google reported 71.0%.
On internal benchmarks, Google reported that Carbon achieves more than 2x uplift in success rate for generating secure code over Argon, and that its Chrome team found Carbon performed more than 10X better than another lab’s large frontier model at generating high-quality patches. Google added that Wiz, its cloud security platform, observes Carbon leading on benchmarks for web penetration testing, a core capability for Wiz’s Scan for Good initiative.
Safety and Alignment Results
Carbon builds on the multi-layered safety and security stack used for Argon, which combines model training, real-time misuse defenses, prompt-injection resilience, and chain-of-thought monitoring, according to Google.
The company reported that Carbon reduced successful cheating on Terminal-Bench 4.0 to 0.0%, with cheating attempts falling to 0.4% while overall accuracy improved, and that high-severity misalignment alerts dropped by almost 80% in live coding environments with internal teams. In internal testing, Google said, Carbon cuts unsupported claims by approximately 2x over Argon, places methodological caveats directly into deliverables, and withholds blocked actions with a clear list of what remains required rather than fabricating or hedging around missing evidence. Google also reported reductions of 26% in overreach and 29% in under-service during multi-step plan execution, and said the model retrieves relevant sources and surfaces discrepancies to the user before acting when tasks are ambiguous. On Gray Swan’s Indirect Prompt Injection Benchmark, Google reported a 0.0% attack success rate for Carbon — resisting every evaluated attack attempt — after Argon previously led the benchmark at 0.7%.
Fairwind Program Access and Pricing
The Fairwind Program, run by Google DeepMind, gives high-priority defenders such as governments, healthcare providers, and telecommunications services early access to advanced models. Google DeepMind states that it currently works with more than 650 partners globally, and that a set of program partners receives exclusive access to Gemini 4 Argon for use with CodeMender, its specialized code security agent for automating software fixes.
Program access carries specific conditions. Partners may carry out only permitted dual-use tasks, including authorized threat simulation, reverse engineering, and malware analysis for defensive and academic research purposes; malicious tasks such as creating malware are not permitted. Participating organizations must apply user-level authentication and phishing-resistant multi-factor authentication, limit model access to internal cybersecurity, incident response, or penetration testing teams, and track employee access and use. Partners may not share, redistribute, or sell access to the models, and Google DeepMind conducts background checks on applicants to verify security history and a record of ethical operations. The program prioritizes governments and national cyber authorities, critical infrastructure operators across healthcare, telecommunications, energy, and financial networks, and core technology platforms.
Carbon launches at the same introductory price as Argon: $2 per million input tokens and $10 per million output tokens, with cached input tokens priced at 95% off the input token price. A footnote in the announcement states that after the introductory period expires, pricing will be $4 per million input tokens and $20 per million output tokens.
Google said it is eager to see how the initial cohort of cyber defenders uses the model and looks forward to bringing Carbon to developers, businesses, and consumers soon.