Claude Opus 5.5 Complete Guide: Pricing, Caching and Calling It on QCode
Anthropic released Claude Opus 5.5 (claude-opus-5-5) on 2026-09-22: 1M context, 128K maximum output, $4 input / $20 output per million tokens, cache reads at $0.20.
Updated 2026-09-29
Four key points
List price per million tokens
$4 in, $20 out per million tokens — 20% below Opus 5, converted from the official price list.
Context / max output
1M tokens of context, up to 128K output tokens per request (official model docs).
Cache reads per million
Cache reads cost $0.20, which the official price list marks at 0.05x base input — 60% below Opus 5, converted from the list.
Claude Code default
Claude Code made claude-opus-5-5 its default Opus in version 2.1.280.
What Claude Opus 5.5 is
Claude Opus 5.5 is the first model in Anthropic's new Claude 5.5 family. The company positions it for complex work that requires careful judgment, and its model docs tell anyone unsure to start here. Against the previous Opus 5, input and output prices are 20% lower and cache reads 60% lower, converted from the official price list.
Why it is worth a look now
Opus 5.5 is the first model in Anthropic's new Claude 5.5 family, released 2026-09-22; the launch post said Sonnet 5.5 and Haiku 5.5 would follow in the coming weeks, and Sonnet 5.5 landed on 2026-09-28. Claude Code has run claude-opus-5-5 as its default Opus since version 2.1.280. As of 2026-09-29, the official model overview still lists Opus 5.5 as the newest Opus.
Public timeline
Anthropic releases Claude Opus 5.5, the first model in the new Claude 5.5 family, at 1M context / 128K output and $4 input / $20 output.
Anthropic releases Claude Sonnet 5.5; the Opus 5.5 launch post had already said Sonnet 5.5 and Haiku 5.5 would follow in the coming weeks.
Check date: Claude Code has shipped claude-opus-5-5 as its default Opus since version 2.1.280, the official model docs point anyone unsure to Opus 5.5 first, and QCode can call it today.
Confirmed vs unverified
Confirmed
Confirmed by official sources: Anthropic released Claude Opus 5.5 on 2026-09-22 under the model ID claude-opus-5-5; 1M context and 128K maximum output; $4 input / $20 output per million tokens; cache reads $0.20, cache writes $5 (5 minutes) / $8 (1 hour); Batch $2 / $10; Fast mode $8 / $40 (in research preview). QCode can call claude-opus-5-5 as of 2026-09-29.
Unverified · Anthropic's numbers only
Unverified: Anthropic says Opus 5.5 performs at the level of Claude Fable 5.1 on most work, costs 40% less to run than Opus 5, and reaches up to 2.5x the speed in Fast mode. All three are the company's own claims, unconfirmed by any third party, and this page carries no rumors or speculation beyond what Anthropic itself claimed. The launch post carries benchmarks; this page does not transcribe them and calls no winner.
Line by line against Opus 5
Opus 5.5 vs Opus 5 (list price)
$4 input, $20 output per million tokens (Opus 5 is $5 / $25); cache reads $0.20 (Opus 5 is $0.50). Converted from the official price list: 20% less on input and output, 60% less on cache reads.
Anthropic's own cost claim vs the price-list cut
Anthropic says running costs on typical workloads are 40% lower than Opus 5 (the company's own testing); the cut on list unit prices is 20% (converted from the official price list). Two different bases — keep them apart.
How to choose, where to start
Here is the start-here line from the official model docs: when you're unsure which model to use, start with Claude Opus 5.5 for most workloads. It is built for complex work that calls for careful judgment. If you would rather pay a higher unit price for faster output, look at Fast mode, which is in research preview.
Using it on QCode
As of 2026-09-29, claude-opus-5-5 is callable on QCode — put that ID in the model parameter of your request. The same key also works in Claude Code and the OpenAI Codex CLI, both pointed at QCode's compatible API, and switching models changes only that parameter. Claude Code has had it as the default Opus since version 2.1.280. Live pricing is on the models page.
FAQ
What does Opus 5.5 cost?
$4 input and $20 output per million tokens; cache reads $0.20, cache writes $5 (5 minutes) / $8 (1 hour); the Batch tier is $2 input / $10 output; Fast mode is $8 / $40. All official list prices, checked 2026-09-29.
Anthropic says 40%, the price list 20% — is it 40% or 20% cheaper than Opus 5?
Converted from the official price list: input and output sit 20% below Opus 5 ($5 to $4, $25 to $20), and cache reads 60% below it ($0.50 to $0.20). Anthropic separately says running costs on typical workloads fall 40% — that is a vendor-claimed running cost, not the same thing as the list-price cut.
How large is the context window, and the maximum output?
A 1M-token context window, with up to 128K tokens of output in a single request (official model docs, released 2026-09-22).
Does Anthropic recommend it as the starting point?
The official model docs say it outright: when you're unsure which model to use, start with Claude Opus 5.5 for most workloads. It is the tier positioned for complex work that calls for careful judgment.
Can I call it on QCode?
Yes. The model ID is claude-opus-5-5, callable on QCode as of 2026-09-29, and the same key covers Claude Code and the Codex CLI, where switching means changing the model parameter. Claude Code has made it the default Opus since version 2.1.280.
What is Fast mode?
Fast mode is Anthropic's option for faster output at a higher price per token. On Opus 5.5 it is priced at $8 / $40 and is in research preview. The official figure is up to 2.5x the speed — that is the vendor's own number, with no third-party check.
Sources
Sources: Anthropic's official model docs (model ID, 1M context / 128K output, the start-here line), the official price list (the Opus 5.5 and Opus 5 rows, the 0.05x cache-read footnote, the Batch and Fast mode tables), the Opus 5.5 launch post ($4 / $20, the 20% and 60% cuts, the claimed 40% saving, Fable 5.1 parity and the claimed up to 2.5x speed), the Sonnet 5.5 launch post (family positioning and the coming-weeks line), and the Claude Code changelog (default Opus from 2.1.280). Checked 2026-09-29.
Try Claude Opus 5.5 right now
One key across the Claude and Codex lineup. As of 2026-09-29, Claude Opus 5.5 is available on QCode with claude-opus-5-5 - signing up is free, and it works as soon as you activate a plan.
Related reading
Claude Opus 5 complete guide
The previous Opus, at $5 input / $25 output — the baseline for this page's comparison.
Claude Sonnet 5 guide
The middle tier at $2 input / $10 output — the value pick for everyday coding.
Claude Haiku 4.5 guide
The light, high-volume tier at $1 input / $5 output, callable on QCode.
QCode is not affiliated with Anthropic. The specs and prices on this page come from Anthropic's official model docs, price list and launch post; the launch post carries benchmarks, which this page does not reproduce. Live pricing is on the models page, checked 2026-09-29.