Gemini 4 Argon vs Claude Opus 5.5: Benchmarks, Pricing and Which to Choose (2026)

Comparing Gemini 4 Argon vs Claude Opus 5.5? These are the two newest frontier models from Google and Anthropic, launched eight days apart, and they lead on different tests. Gemini 4 Argon tops Vals AI’s overall index and is much cheaper until the end of November, while Claude Opus 5.5 scores higher on Artificial Analysis’s index and on terminal-based coding work. This comparison sets out the benchmarks, API prices, subscription access, coding tools and limits side by side, so you can decide which model fits your work.

Prices, access rules and benchmark scores were checked on 14 October 2026 against Google’s and Anthropic’s official pages and the public results published by Vals AI and Artificial Analysis. We have not run our own head-to-head tests, so every benchmark figure is attributed to its source. API prices are in US dollars and exclude VAT.

Gemini 4 Argon vs Claude Opus 5.5: Quick Verdict

• Choose Gemini 4 Argon for financial and legal analysis, very long documents or video, Google Workspace users, and API workloads where cost matters, especially before 1 December.
• Choose Claude Opus 5.5 for terminal-based and agentic coding, multimodal software engineering tasks, and if you want a capable coding agent on a $20 subscription through Claude Code.
• Test both if you build on the API: after 1 December their list prices are identical, so real results on your own tasks should decide.

What Is Gemini 4 Argon?

Gemini 4 Argon is Google DeepMind’s flagship model, which Google describes as its “frontier model for real-world coding, enterprise knowledge work, and cyber defense”. Google announced it on 30 September 2026 for selected cybersecurity partners and made it widely available on 13 October to Google AI Pro and Ultra subscribers in the Gemini app and to paid users of the Gemini API. It accepts text, images, video, audio and PDFs, has a 1,048,576-token context window shared between input and output, and offers three thinking levels: low, medium and high.

What Is Claude Opus 5.5?

Claude Opus 5.5 is Anthropic’s latest Opus model, released on 22 September 2026 for long-running coding, agents and knowledge work. Anthropic’s models overview lists a 1M token context window, up to 128K output tokens, a reliable knowledge cutoff of June 2026 and adaptive thinking that is always on, with medium as the default effort. Anthropic says it costs an estimated 40% less to run than Opus 5 for typical workloads. It is available on paid Claude plans, in Claude Code, through the Claude API and on major cloud platforms.

Side-by-Side Comparison

Gemini 4 Argon vs Claude Opus 5.5 Benchmarks: Who Wins?

The honest answer is that it depends on the test. Here are the results from independent evaluators first, then each company’s own claims.

Independent results from Vals AI

Vals AI’s pages show some inconsistencies between their score tables and update notes, so we have used the figures in each model’s main table. Small differences, such as Code Migration and Vibe Code Bench, are within the stated margins of error.

Artificial Analysis Intelligence Index

Artificial Analysis combines many tests into one score. According to VentureBeat’s report of its results, Claude Opus 5.5 scores 58, while Gemini 4 Argon scores 53, the same as OpenAI’s GPT-6 Astra and Anthropic’s Claude Fable 5.1. Artificial Analysis also notes that Argon is “somewhat verbose”, generating 110 million tokens on its index compared with a median of 85 million.

What Google and Anthropic claim

Google’s launch table, as reported by VentureBeat, shows Argon ahead on DeepSWE v1.1 (77.9% vs 74.2%), Zapier’s AutomationBench (51.3% vs 42.5%) and Harvey’s legal benchmark, but behind Opus 5.5 on Terminal-Bench 4.0 (57.4% vs 66.4%). Anthropic, for its part, highlights efficiency: it says Opus 5.5 costs an estimated 40% less to run than Opus 5 for typical workloads, and customers report it matching Opus 5’s coding quality in about half the turns and tokens. Treat each company’s figures as claims until more independent testing is available.

What the benchmarks suggest

• Argon leads on finance, legal, cybersecurity and overall professional-work indexes.
• Opus 5.5 leads on long command-line coding tasks and multimodal software engineering, and on Artificial Analysis’s general intelligence index.
• Both are close on code migration and app-building tests.

Gemini 4 Argon vs Claude Opus 5.5 Pricing

API pricing

Until 30 November 2026, Argon costs half as much as Opus 5.5 per token: $2 input and $10 output, against $4 and $20. From 1 December, Argon rises to $4 and $20, matching Opus 5.5 exactly.

These are our own calculations from the list prices, before caching, batch discounts or VAT. In practice, total cost also depends on how many tokens each model uses. Vals AI’s runs cost less with Argon ($15.68 per Vals Index test against $32.14 for Opus 5.5), while Artificial Analysis found Argon more verbose than average, so measure token use on your own workload.

Other pricing options:

• Argon: Batch and Flex processing cost half the standard rate, and Priority costs more ($3.60 / $18 until 30 November). Google Search grounding includes 5,000 free requests a month, then $14 per 1,000.
• Opus 5.5: Fast mode, up to 2.5 times faster in Claude Code and on the Claude Platform, costs $8 / $40. US-only inference costs 1.1 times the standard price.

For comparison, VentureBeat lists OpenAI’s GPT-6 Astra at $10 input and $50 output, so both models are considerably cheaper than Astra at list price.

Subscription pricing

Anthropic quotes Claude prices in US dollars, with UK tax added at checkout. Our Gemini pricing guide and Claude pricing guide break down every plan.

Coding: Antigravity vs Claude Code

For developers, the coding tools matter as much as the models.

• Gemini 4 Argon in Antigravity: Google’s agent-first development platform, available as a desktop app and terminal CLI, with Android tooling through a plugin. Argon is only available there on Google AI Ultra. Paid API users can also use Argon directly in Android Studio and through Firebase AI Logic.
• Claude Opus 5.5 in Claude Code: Anthropic’s agentic coding tool runs in the terminal, IDEs, desktop app and browser, and is included from the $20 Claude Pro plan. Our Claude Code beginner’s guide explains setup, and our Cursor vs Claude Code comparison covers another popular way to use Claude models.

On cost of entry, Claude has the advantage for individual developers: a coding agent with Opus 5.5 starts at $20 a month, while Argon in Antigravity needs Google AI Ultra. On the benchmarks, Opus 5.5 also leads on Vals AI’s Terminal-Bench 4.0 and SWE-bench Multimodal results, while Argon is slightly ahead on Code Migration.

Context Window, Multimodality and Speed

• Context: both offer about 1 million tokens. Argon’s documentation is more specific, stating 1,048,576 tokens shared between input and output, with long outputs of up to about 1 million tokens through long decode.
• Inputs: Argon accepts video and audio as well as text, images and PDFs, and scored 91.7% on the LVBench long-video test in Google’s results. Anthropic describes Opus 5.5 as strong at reading dense documents, charts and screenshots and at computer use, and does not list video or audio input.
• Speed: Vals AI lists an average latency of 46 minutes 33 seconds for Argon and 79 minutes for Opus 5.5 across its benchmark runs. Artificial Analysis measured Argon at about 100 to 117 output tokens per second, depending on the provider. Opus 5.5 offers a paid Fast mode for quicker responses.

Safety, Privacy and Availability

• Security focus: Google trained Argon for defensive cybersecurity and released a version without cyber guardrails only to vetted defenders in its Fairwind Program. The public version refuses harmful cyber and CBRN requests and uses misalignment monitoring.
• Anthropic safeguards: Anthropic says Opus 5.5 is the first Opus model to launch with safeguards similar to Claude Fable 5.1 for cybersecurity, biology and anti-distillation.
• Data location: Anthropic offers US-only inference for Opus 5.5 at 1.1 times standard pricing. Google’s Argon announcements do not cover regional data residency, so businesses with UK or EU data requirements should check Google Cloud’s regional options or Anthropic’s cloud partners before choosing.
• Regions: Google describes the developer release as available globally. Neither company’s announcement lists UK or EU restrictions for these models.

Whichever model you choose, an AI agent that can run code or access data needs guardrails. Our AI agent security guide explains the essentials.

Strengths and Weaknesses

Gemini 4 Argon

• Strengths: leads Vals AI’s overall index and its finance, legal and cybersecurity tests; half the per-token price of Opus 5.5 until 30 November; accepts video and audio as well as text, images and PDFs; very long outputs through long decode; Batch and Flex processing at half the standard rate.
• Weaknesses: Artificial Analysis found it more verbose than average; it trails Opus 5.5 on Terminal-Bench 4.0 and SWE-bench Multimodal; Antigravity and AI Studio access need Google AI Ultra or a paid API account; its API price doubles on 1 December; implicit caching only and no Live API support.

Claude Opus 5.5

• Strengths: the higher score of the two on Artificial Analysis’s Intelligence Index; leads on Terminal-Bench 4.0 and SWE-bench Multimodal in Vals AI’s results; available in Claude Code from the $20 Claude Pro plan; up to 128K output tokens; available on Amazon Web Services, Google Cloud and Microsoft Foundry as well as Anthropic’s own API.
• Weaknesses: twice Argon’s per-token price until 30 November; higher cost per test and latency in Vals AI’s runs; a low score on Harvey’s Legal Agent Benchmark (3.75%); Anthropic does not list video or audio input; Fast mode doubles the price.

Use Cases: Gemini 4 Argon vs Claude Opus 5.5 in Practice

For developers

For multi-file refactors, debugging and long terminal sessions, Opus 5.5 in Claude Code is the more accessible choice and leads the relevant command-line benchmarks. Argon suits large code migrations and long-context code review, Android developers who work in Android Studio or Firebase, and high-volume batch jobs that benefit from its introductory pricing and half-price Batch tier.

For businesses

Firms that analyse financial statements, contracts or compliance documents should test Argon first, given its lead on Vals AI’s finance and legal benchmarks, especially if they already use Google Workspace or Gemini Enterprise. Organisations that buy AI through Amazon Web Services or Microsoft, or already use Claude for work, may find Opus 5.5 easier to adopt. Either way, review the data terms and processing locations before sending client data.

For individual users

If you mainly use AI in a chat app, Google AI Pro (£18.99 a month in the UK) gives you Argon alongside Gemini in Gmail, Docs and Sheets, while Claude Pro ($20 a month plus tax) gives you Opus 5.5 and Claude Code. Neither model is available on a free plan, so free users should start with the free tiers of the Gemini app or Claude instead.

Which Should You Choose?

If you choose Argon, our step-by-step guide on how to use Gemini 4 Argon covers the Gemini app, AI Studio, the API and Antigravity.

Frequently Asked Questions

Is Gemini 4 Argon better than Claude Opus 5.5?

Not across the board. Argon leads Vals AI’s overall index and its finance, legal and cybersecurity tests, while Opus 5.5 leads Artificial Analysis’s Intelligence Index and coding tests such as Terminal-Bench 4.0 and SWE-bench Multimodal.

Which is cheaper, Gemini 4 Argon or Claude Opus 5.5?

Until 30 November 2026, Argon costs half as much per token ($2 / $10 vs $4 / $20). From 1 December, both have the same list price of $4 input and $20 output per million tokens.

Which is better for coding?

Opus 5.5 leads on Vals AI’s Terminal-Bench 4.0 and SWE-bench Multimodal results and is available in Claude Code from $20 a month. Argon is slightly ahead on code migration and leads Google’s DeepSWE results, but its Antigravity access requires Google AI Ultra.

Can I use either model for free?

No. Argon needs Google AI Pro or Ultra or a paid API account, and Opus 5.5 needs a paid Claude plan or API credits.

What are the context windows of Gemini 4 Argon and Claude Opus 5.5?

Both offer about 1 million tokens. Google lists 1,048,576 tokens shared between input and output for Argon, with 65,536 output tokens by default and up to about 1 million with long decode. Anthropic lists a 1M token context window and up to 128K output tokens for Opus 5.5.

How does GPT-6 Astra compare?

Artificial Analysis scores GPT-6 Astra 53, level with Argon and below Opus 5.5, and VentureBeat lists its API price at $10 input and $50 output per million tokens, making it the most expensive of the three.

Conclusion

The Gemini 4 Argon vs Claude Opus 5.5 decision comes down to your work. Argon is the stronger pick for finance, legal and long multimodal tasks, and it is much cheaper until the end of November. Opus 5.5 is the safer choice for agentic coding and is easier to access for individual developers through Claude Code. Because their API list prices match from 1 December, run both on a sample of your real tasks during November and keep the one that gives better results for the tokens it uses.

Sources: Google – Gemini 4 Argon announcement; Gemini API – Gemini 4 Argon model page; Gemini API pricing; Android Developers Blog; Anthropic – Claude Opus; Anthropic – models overview; Claude pricing; Vals AI – Gemini 4 Argon; Vals AI – Claude Opus 5.5; Artificial Analysis – Gemini 4 Argon; Artificial Analysis – Argon providers; VentureBeat; TechCrunch.