Overview
Claude Sonnet 5 launched on June 30, 2026 as Anthropic's most agentic Sonnet model at the time. Gemini 4 Argon became generally available on October 13, 2026. They are often compared because both currently list at the same token price.
Pricing
Gemini 4 Argon: $2 per 1M input tokens and $10 per 1M output tokens through November 30, 2026, then $4 and $20.Claude Sonnet 5: $2 per 1M input tokens and $10 per 1M output tokens. On August 10, 2026 Anthropic made this introductory price permanent and dropped the planned $3 / $15 rate.Capabilities
Argon accepts text, image, video, audio and PDF input, has a 1,048,576-token unified context window, and offers long decode up to 1,048,576 output tokens.Sonnet 5 accepts text and images, has a 1M-token context window and 128K max output, uses adaptive thinking with default effort high, and has a January 2026 knowledge cutoff.Anthropic says Sonnet 5's performance is close to Claude Opus 4.8. Google says Argon ranks first on the Vals Index. Neither company publishes a direct head-to-head score.Status
Sonnet 5 is now a legacy model. Anthropic recommends moving to Claude Sonnet 5.5, released September 28, 2026 at the same $2 / $10 price. Sonnet 5 stays available until at least June 30, 2027.
How to choose
If you compare these two on cost alone, plan for Argon's price to double on December 1, 2026.For new Claude-based projects, compare Argon with Claude Sonnet 5.5 rather than Sonnet 5.No hands-on testing was conducted for this comparison. Every figure above comes from the official pages listed under Research sources, as published on or before October 22, 2026. Where a vendor has not published a number, we say so instead of estimating it.