Updated August 2026

Claude Opus 5 API Access in 2026

Claude Opus 5 is Anthropic's most capable model for deep reasoning, agentic coding, long-horizon tasks, and enterprise work. Through Claude API Tech, Opus 5 is available without a separate subscription.

One key, all models

A sk-cs2-* key gives access to Opus 5, Fable 5, Opus 4.8, Sonnet 5, and every other supported model. Switch models by changing the model parameter — no new key required.

Available models

ModelInputOutputContext
NEWClaude Fable 5
$5.00 / 1M$25.00 / 1M200K
NEWClaude Opus 5
$2.50 / 1M$12.50 / 1M1M
OPUSClaude Opus 4.8
$2.50 / 1M$12.50 / 1M200K
OPUSClaude Opus 4.7
$2.50 / 1M$12.50 / 1M200K
OPUSClaude Opus 4.6
$2.50 / 1M$12.50 / 1M200K
OPUSClaude Opus 4.5
$2.50 / 1M$12.50 / 1M200K
NEWClaude Sonnet 5
$1.00 / 1M$5.00 / 1M200K
FASTClaude Sonnet 4.6
$1.50 / 1M$7.50 / 1M200K
FASTClaude Sonnet 4.5
$1.50 / 1M$7.50 / 1M200K

Claude Opus 5 — specifications

Context window
1,000,000 tokens
Max output
128,000 tokens
Input
$2.50 / 1M tokens
Output
$12.50 / 1M tokens
Extended Thinking
Supported
API formats
Anthropic + OpenAI-compat
Streaming
SSE supported

Best use cases

  • Complex architecture and code review
  • Long document analysis (1M context)
  • Premium reasoning and research
  • Extended Thinking for multi-step problems
  • Production AI agents with deep reasoning

About pricing

At Claude API Tech you pay for Anthropic-equivalent tokens at up to −50% vs official. Tokens never expire. No monthly fee.

Access Opus 5 API$0.25 bonus on signup · No card required