ANTHROPIC · FRONTIER FLAGSHIP: CLAUDE OPUS 5.5 · CHECKED 2026-11-05
Anthropic: Claude Opus 5.5 & 2026 Buyer's Verdict
Anthropic last shipped Claude Haiku 5.5 on Oct 7, 2026, 30 days ago. Its last 4 release gaps were 39, 21, 6, 9 days, so a typical gap is about 15 days. No next model announced as of Nov 5, 2026.
1. SOURCED 2026 RELEASE TIMELINE (11 RELEASES)
Every 2026 Anthropic Release With Primary Source
Only public API and open-weight releases count toward the cadence calculation. Gated previews and app-only launches are listed for context and marked accordingly.
| RELEASE DATE | MODEL | RELEASE TYPE | GAP FROM PRIOR PUBLIC DROP | PRIMARY SOURCE |
|---|---|---|---|---|
| 2026-02-05 | Claude Opus 4.6 | API release | First 2026 baseline | platform.claude.com ↗ |
| 2026-02-17 | Claude Sonnet 4.6 | API release | 12d [source] | platform.claude.com ↗ |
| 2026-04-16 | Claude Opus 4.7 | API release | 58d [source] | platform.claude.com ↗ |
| 2026-05-28 | Claude Opus 4.8 | API release | 42d [source] | platform.claude.com ↗ |
| 2026-06-09 | Claude Fable 5 | API release | 12d [source] | anthropic.com ↗ |
| 2026-06-30 | Claude Sonnet 5 | API release | 21d [source] | anthropic.com ↗ |
| 2026-07-24 | Claude Opus 5 | API release | 24d [source] | anthropic.com ↗ |
| 2026-09-01 | Claude Fable 5.1 | API release | 39d [source] | techcrunch.com ↗ |
| 2026-09-22 | Claude Opus 5.5 | API release | 21d [source] | anthropic.com ↗ |
| 2026-09-28 | Claude Sonnet 5.5 | API release | 6d [source] | anthropic.com ↗ |
| 2026-10-07 | Claude Haiku 5.5 | API release | 9d [source] | anthropic.com ↗ |
2. CURRENT MODELS, BENCHMARKS & API PRICING
Current Anthropic Models a Buyer Can Use Today
Every score and price links directly to its source (LMArena text leaderboard (Oct 27, 2026), Epoch AI, Artificial Analysis, or official lab documentation). Unpublished metrics are left as "Not published".
| MODEL & RELEASE DATE | INPUT / OUTPUT ($/1M) | CONTEXT | ARENA TEXT ELO | GPQA DIAMOND | OUTPUT SPEED |
|---|---|---|---|---|---|
|
Claude Opus 5.5 ↗
FRONTIER FLAGSHIP
Released 2026-09-22
· Effort: low · medium · high · xhigh · max (
output_config={"effort": "low" | "medium" | "high" | "xhigh" | "max"} docs ↗)
Best at: Anthropic suggests starting with Opus 5.5 for most workloads. #1 on Arena WebDev (1810); 66.4% on Terminal-Bench 4.0 at xhigh effort (Anthropic). ↗
Additional evals: Arena WebDev: 1810 (#1) (Arena) ↗ · SWE-bench Pro: 89.9% (Anthropic system card) ↗ · Terminal-Bench 4.0: 66.4% (xhigh) (Anthropic) ↗ · GDPval-AA v2.1: 1846 (Anthropic) ↗ · CursorBench 4.0: 57.8% at max effort, 52.5% at default (Anthropic) ↗ · AA Intelligence Index v5.0.1: 59 (Artificial Analysis) ↗
|
$4.00 / $20.00 ↗
Same rate across the full 1M context window.
|
1M ↗ | 1509 ↗ | 90.6% (Epoch AI, max effort) ↗ | 110 tok/s (AA) ↗ |
|
Claude Fable 5.1 ↗
TIER MODEL
Released 2026-09-01
· Effort: low · medium · high · xhigh · max (
output_config={"effort": "low" | "medium" | "high" | "xhigh" | "max"} docs ↗)
Best at: Anthropic's most capable generally available model, for demanding reasoning and long-horizon agentic work (Anthropic). ↗
Additional evals: Terminal-Bench 4.0: 55.8% (Anthropic) ↗ · GDPval-AA v2.1: 1735 (Anthropic) ↗ · AA Intelligence Index v5.0.1: 50 (Artificial Analysis) ↗
|
$10.00 / $50.00 ↗
Same rate across the full 1M context window.
|
1M ↗ | 1504 ↗ | Not published | Not published |
|
Claude Sonnet 5.5 ↗
TIER MODEL
Released 2026-09-28
· Effort: low · medium · high · xhigh · max (
output_config={"effort": "low" | "medium" | "high" | "xhigh" | "max"} docs ↗)
Best at: Fast (155 tok/s, Artificial Analysis) and strong on science: 95.6% GPQA Diamond at max effort (Epoch AI), above Opus 5.5's 90.6%. ↗
Additional evals: SWE-bench Pro: 81.3% (Anthropic system card) ↗ · AA Intelligence Index v5.0.1: 55 (Artificial Analysis) ↗
|
$2.00 / $10.00 ↗
Same rate across the full 1M context window.
|
1M ↗ | 1477 ↗ | 95.6% (Epoch AI, max effort) ↗ | 155 tok/s (AA) ↗ |
3. NEXT-RELEASE FORECAST & PLAIN-LANGUAGE METHOD
How We Estimate the Next Anthropic Release Window
Plain-language method: We take the last 4 public release gaps for Anthropic:
The shortest of those 4 gaps is 6 days, the median is 15 days, and the longest is 39 days. Adding those intervals to Claude Haiku 5.5 (2026-10-07) places the historical cadence window between 2026-10-13 and 2026-11-15 (median date: 2026-10-22). Rough estimate from 4 gaps ranging 6 to 39 days. Labs do not follow schedules.
Official Statements & Labeled Rumors
No official next-release announcement or verified press rumor is currently on file for this lab.