Claude Haiku 5.5 vs Claude Opus 5

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 5 when a specific cost or latency profile matters more than the latest capabilities.

Claude Haiku 5.5 and Claude Opus 5 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 5 is anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak. 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

Side-by-side specs

SpecClaude Haiku 5.5Claude Opus 5
ProviderAnthropic (US) Anthropic (US)
ReleasedOctober 7, 2026 July 24, 2026
Context window1M 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
Modalitiestext, image, code text, image, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

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 5 is comparatively weak here — fast mode's throughput costs double the base price ($10/$50 per 1M)

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 5 ($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 5 is comparatively weak here — behind Mythos 5 on cybersecurity exploitation and biology research, by Anthropic's own account

Frontier reasoning at lower cost per task — Anthropic reports it more than doubling Opus 4.8 on Frontier-Bench v0.1

Claude Opus 5

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

Agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures)

Claude Opus 5

Claude Opus 5 lists agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures) among its strengths; Claude Haiku 5.5 does not.

Computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost

Claude Opus 5

Claude Opus 5 lists computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost among its strengths; Claude Haiku 5.5 does not.

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 5, 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 frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1

→ Claude Opus 5

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 5: where it fits

Anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak. Released July 24, 2026 by Anthropic, it is built for frontier reasoning at lower cost per task — Anthropic reports it more than doubling Opus 4.8 on Frontier-Bench v0.1, agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures), computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost, and a native effort setting (low, medium, high, xhigh, max) that trades token cost against capability on a single model.

Its trade-offs: behind Mythos 5 on cybersecurity exploitation and biology research, by Anthropic's own account, all launch benchmarks are Anthropic-reported and not yet independently reproduced, no published SWE-Bench Verified score, so head-to-head coding comparisons rely on Anthropic's own benchmark suite, and fast mode's throughput costs double the base price ($10/$50 per 1M). 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 5 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 pricing

Frequently asked questions

Is Claude Haiku 5.5 or Claude Opus 5 better for coding?

Public SWE-Bench figures are not available for either model, 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 5 leans toward frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Haiku 5.5 or Claude Opus 5?

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 5 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 5?

Claude Haiku 5.5 — released October 7, 2026, about 3 months after Claude Opus 5.

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.