I Tested Opus 5.5 So You Don't Have To...

Summary
This video is a hands-on review and "vibe coding" evaluation of Anthropic's Claude Opus 5.5 presented by an independent tech creator. The host demonstrates three web applications generated with Claude Opus 5.5—a 3D flight simulator, an interactive 3D economic report webpage, and a physics simulation—and compares its speed and output against previous models like Claude Opus 5 and Claude Fable 5.1 before reviewing Anthropic's announcement blog post.

What is shown

• [00:00] Overview of Anthropic's announcement page for Claude Opus 5.5.
• [00:46] Demonstration of "Night Flyover", a 3D city flight simulator built with Claude Opus 5.5 featuring customizable camera views (Chase, Look down, Left, Right, Front, Cinematic) and telemetry gauges.
• [01:43] Demonstration of "The economy after AI", an interactive webpage featuring rotating 3D particle spheres, 3D bar graphs, interactive carousel cards, and structured text sections generated in a single prompt.
• [02:43] Interactive physics demonstration of a "Double Pendulum" simulation with controls for pendulum count, spread, gravity, mass ratio, trail length, and speed.
• [03:40] Walkthrough of Anthropic’s official release blog post, detailing benchmark scores, safety audits, coding migration case studies, and pricing tables.

Claims & numbers

• The presenter and blog post state that Claude Opus 5.5 performs at the level of Claude Fable 5.1 on most work while costing 40% less to run than Claude Opus 5.
• The presenter claims generating the flight simulator took under 3 to 4 minutes with Opus 5.5, compared to over 10 minutes with Opus 5 and Fable 5.1.
• The presenter notes that the interactive economic website was generated in "one shot" in less than two minutes.
• The Anthropic blog post cited in the video claims:
  • An early tester completed a 680,000-line codebase migration in less than a day using Opus 5.5.
  • Succeeded 39 out of 40 times in finding and fixing inefficiencies in web apps, whereas Opus 5 succeeded 30 of 40 times.
  • Opus 5.5 scored 66.4% on Terminal-Bench 4.0 (versus 58.0% for Fable 5.1 and 52.3% for Opus 5) and 54.4% on FrontierCode v1.1 (Main).
  • Pricing is set at $4 per million input tokens, $20 per million output tokens, $0.20 per million cache reads, and $5 per million cache writes (20% less than Opus 5 for prompt caching reads and 40% cheaper overall on typical workloads).
  • Five-hour usage limits on Pro, Max, and Team tiers are increased by 5x compared to Opus 5.

Notable quotes

• [00:19] "Opus 5.5 is revolutionary, and the reason I'm saying that, and specifically for this model, is because it is the first model that Anthropic has released since they called for pacing the frontier."
• [01:00] "So in terms of speed, this was much better. This took less than three or four minutes, whereas Opus 5 and Fable both took over 10 minutes to build this same thing."
• [03:43] "Personally, I don't believe in benchmarks. I believe in testing, which is why we tested out the model before we started reading..."

Assessment
This is an independent user review and real demonstration examining Claude Opus 5.5 through generated browser artifacts and Anthropic's release documentation. The generation process itself is not shown in real-time (the applications are demonstrated pre-rendered), but the applications are fully functional and interactive on screen.

Described by gemini-3.8-flash on 2026-09-29 from the video's audio and frames.