Anthropic Releases Claude Opus 5 at Half the Token Price of Claude Fable 5

Anthropic has launched Claude Opus 5, offering token pricing at half the rate of Claude Fable 5 and claiming near-frontier performance, according to Anthropic and The Register.

Opus 5 is priced at $5 per million input tokens and $25 per million output tokens, compared to $10 and $50 for Fable 5. Anthropic states the model "comes close to the frontier intelligence of Claude Fable 5 at half the price." Opus 5 does not require data retention.

Anthropic describes Opus 5 as its "most aligned model to date." The company reports it outperforms Opus 4.8 overall, with the greatest improvements in agentic coding, computer use, and long-horizon knowledge work.

Pricing and Benchmark Position, Shorter System Prompt and Changed Context Guidance

Fable 5 is priced at $10 per million input tokens and $50 per million output tokens, while Opus 5 is $5 and $25. For comparison, The Register notes that OpenAI's GPT-5.6 Sol costs $5 per million input tokens and $30 per million output tokens.

Since token usage per task varies by model, per-task cost is a distinct metric. Artificial Analysis reports the weighted average cost per Intelligence Index task as $2.75 for Fable, $2.03 for Opus 5 at maximum settings, $1.04 for GPT-5.6 Sol at maximum settings, and $0.95 for Kimi K3. Opus 5 leads the Artificial Analysis Intelligence Index with a score of 61, one point ahead of Fable.

Anthropic claims Opus 5 "provides greatly improved performance for the same cost as its predecessor, Opus 4.8." The system card states it is comparable to, and in some cases surpasses, Claude Fable 5 and Claude Mythos 5.

Anthropic has reduced the system prompt size in its latest models. Claude Code engineer Thariq Shihipar states that 80 percent of the Claude Code system prompt was removed, allowing customers more context to use. Consequently, Anthropic has updated its guidance for crafting prompts, skills, and CLAUDE.md files.

"Across your system prompt, skills, and CLAUDE.md files, you may need to simplify just like we did,"…