Claude Haiku 5.5 vs Claude Opus 4.6
Anthropic · US | Anthropic · US · Updated June 2026
Quick verdict
Both are Anthropic models. Claude Haiku 5.5 is the newer, generally stronger default; reach for Claude Opus 4.6 when a specific cost or latency profile matters more than the latest capabilities.
Claude Haiku 5.5 and Claude Opus 4.6 are both Anthropic models, so the real question is not which lab to trust but which tier fits your workload and budget. Claude Haiku 5.5 is anthropic's October 7, 2026 small-model refresh — a 1M-token context window (up from 200K) at roughly 75% lower average cost than Haiku 4.5, priced at $0.10/$0.50 per million tokens. Claude Opus 4.6 is anthropic's February 2026 flagship Opus and the first Opus-class model with a 1M-token context window, built for agentic coding and long-running professional tasks. Since both come from the same lab, the comparison below focuses on the tier-and-cost trade-offs that actually separate them.
Key differences at a glance
- ▸Price: Claude Haiku 5.5 is about 50× cheaper on input ($0.1/$0.5 per 1M tokens vs $5/$25 per 1M tokens) — a large enough gap that at scale it can be the single biggest line item in the decision.
- ▸Context window: both advertise 1M tokens (~1,500 pages). Tie on paper — test on your own long inputs, since usable recall varies by model.
- ▸Recency: Claude Haiku 5.5 is the newer model by about 8 months (released October 7, 2026), usually meaning fresher training data and capabilities.
Side-by-side specs
| Spec | Claude Haiku 5.5 | Claude Opus 4.6 |
|---|---|---|
| Provider | Anthropic (US) | Anthropic (US) |
| Released | October 7, 2026 | February 5, 2026 |
| Context window | 1M tokens (~1,500 pages) | 1M (~1,500 pages) |
| Price (in/out) | $0.1/$0.5 per 1M tokens | $5/$25 per 1M tokens |
| Open weight? | No — API only | No — API only |
| Modalities | text, image, code | text, image, code |
| SWE-Bench Verified | Not published | 80.8% |
| MRCR v2 @ 1M | Not published | 76% |
Who wins what
5x the context window of Haiku 4.5 (1M vs 200K tokens) and double the max output (128K vs 64K)
Claude Haiku 5.5
Claude Opus 4.6 is comparatively weak here — top-tier per-token price, and its 1M-token context shipped as beta
First Haiku-class model with an adjustable 'effort' setting to trade off cost, latency, and intelligence
Claude Haiku 5.5
At $0.1/$0.5 per 1M tokens it undercuts Claude Opus 4.6 ($5/$25 per 1M tokens), and that gap compounds at volume.
Anthropic's cheapest small model yet — runs about 75% cheaper on average than Haiku 4.5
Claude Haiku 5.5
Claude Opus 4.6 is comparatively weak here — superseded by newer Claude Opus 4.7 and 4.8 (now a legacy model)
Agentic coding and debugging in large codebases
Claude Opus 4.6
Claude Opus 4.6 lists agentic coding and debugging in large codebases among its strengths; Claude Haiku 5.5 does not.
Long-running, multi-step autonomous agent tasks
Claude Opus 4.6
Claude Opus 4.6 lists long-running, multi-step autonomous agent tasks among its strengths; Claude Haiku 5.5 does not.
Frontier multidisciplinary reasoning (leads Humanity's Last Exam)
Claude Opus 4.6
Claude Haiku 5.5 is comparatively weak here — as the smallest tier, trails both Sonnet 5.5 and Opus 5.5 on hard reasoning and open-ended work
Lowest cost at scale
Claude Haiku 5.5
At $0.1/$0.5 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.
Which should you pick?
A cost-sensitive startup shipping high volume
→ Claude Haiku 5.5
At $0.1/$0.5 per 1M tokens it undercuts Claude Opus 4.6, and on millions of tokens that margin decides the monthly bill.
Anyone whose priority is 5x the context window of haiku 4.5 (1m vs 200k tokens) and double the max output (128k vs 64k)
→ Claude Haiku 5.5
It is specifically built for that.
Anyone whose priority is agentic coding and debugging in large codebases
→ Claude Opus 4.6
That is its strongest area.
Claude Haiku 5.5: where it fits
Anthropic's October 7, 2026 small-model refresh — a 1M-token context window (up from 200K) at roughly 75% lower average cost than Haiku 4.5, priced at $0.10/$0.50 per million tokens. Released October 7, 2026 by Anthropic, it is built for 5x the context window of Haiku 4.5 (1M vs 200K tokens) and double the max output (128K vs 64K), first Haiku-class model with an adjustable 'effort' setting to trade off cost, latency, and intelligence, anthropic's cheapest small model yet — runs about 75% cheaper on average than Haiku 4.5, and over-refuses benign requests only 0.17% of the time on the API, down from Haiku 4.5's 0.44%.
Its trade-offs are real: pricing jumps roughly 5x beyond 100K-token prompts ($0.50/$2.50 per million vs the headline $0.10/$0.50), extended thinking can no longer be fully disabled — only dialed between low, medium, and high effort, and as the smallest tier, trails both Sonnet 5.5 and Opus 5.5 on hard reasoning and open-ended work. At $0.1 in / $0.5 out per million tokens, it sits in the budget price band.
Claude Opus 4.6: where it fits
Anthropic's February 2026 flagship Opus and the first Opus-class model with a 1M-token context window, built for agentic coding and long-running professional tasks. Released February 5, 2026 by Anthropic, it is built for agentic coding and debugging in large codebases, long-running, multi-step autonomous agent tasks, frontier multidisciplinary reasoning (leads Humanity's Last Exam), and economically valuable knowledge work in finance and legal (GDPval-AA).
Its trade-offs: superseded by newer Claude Opus 4.7 and 4.8 (now a legacy model), and top-tier per-token price, and its 1M-token context shipped as beta. At $5 in / $25 out per million tokens, it sits in the premium price band.
The bottom line for this matchup
Because Claude Haiku 5.5 and Claude Opus 4.6 come from the same lab (Anthropic), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. Claude Haiku 5.5 is the more capable, more recent option; the other earns its place only when its price or latency profile fits a specific job better. Most teams should default to Claude Haiku 5.5 and drop down only with a concrete reason.
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See pricingFrequently asked questions
Is Claude Haiku 5.5 or Claude Opus 4.6 better for coding?
Public SWE-Bench figures are not available for Claude Haiku 5.5, so the honest test is your own repository — run an identical real bug through both. By design, Claude Haiku 5.5 leans toward 5x the context window of haiku 4.5 (1m vs 200k tokens) and double the max output (128k vs 64k) while Claude Opus 4.6 leans toward agentic coding and debugging in large codebases, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, Claude Haiku 5.5 or Claude Opus 4.6?
Claude Haiku 5.5 is cheaper — $0.1/$0.5 per 1M tokens vs $5/$25 per 1M tokens, roughly 50× apart on input.
Which has the bigger context window?
Both advertise 1M tokens (~1,500 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.
Should I upgrade from Claude Opus 4.6 to Claude Haiku 5.5?
Since both are Anthropic models, the newer one (Claude Haiku 5.5) is usually the better default unless you need a specific cost or latency profile from the other.
Which is newer, Claude Haiku 5.5 or Claude Opus 4.6?
Claude Haiku 5.5 — released October 7, 2026, about 8 months after Claude Opus 4.6.
Related comparisons
Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.