Claude Haiku 5.5 vs GPT-5.4 Nano

Anthropic · US  |  OpenAI · US · Updated June 2026

Quick verdict

Pick Claude Haiku 5.5 for 5x the context window of haiku 4.5 (1m vs 200k tokens) and double the max output (128k vs 64k) or first haiku-class model with an adjustable 'effort' setting to trade off cost, latency, and intelligence. Pick GPT-5.4 Nano for cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work or classification, extraction, ranking and sub-agent execution at scale. On a tight budget at scale, Claude Haiku 5.5 is the value pick.

Claude Haiku 5.5 (Anthropic) and GPT-5.4 Nano (OpenAI) are two of the models people most often weigh against each other in 2026. 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. GPT-5.4 Nano is openAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning. They diverge most on price and context window — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecClaude Haiku 5.5GPT-5.4 Nano
ProviderAnthropic (US) OpenAI (US)
ReleasedOctober 7, 2026 March 17, 2026
Context window1M tokens (~1,500 pages) 400K (~600 pages)
Price (in/out)$0.1/$0.5 per 1M tokens $0.2/$1.25 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

Its 1M tokens window holds about 2.5× more than GPT-5.4 Nano's 400K in a single prompt.

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 GPT-5.4 Nano ($0.2/$1.25 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

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 — and it runs cheaper at $0.1/$0.5 per 1M tokens.

Cheapest GPT-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work

GPT-5.4 Nano

GPT-5.4 Nano lists cheapest GPT-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work among its strengths; Claude Haiku 5.5 does not.

Classification, extraction, ranking and sub-agent execution at scale

GPT-5.4 Nano

GPT-5.4 Nano lists classification, extraction, ranking and sub-agent execution at scale among its strengths; Claude Haiku 5.5 does not.

A 400K context in the smallest, fastest GPT-5.4 variant

GPT-5.4 Nano

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.

Largest single-prompt input

Claude Haiku 5.5

Its 1M tokens window is about 2.5× larger than GPT-5.4 Nano's 400K, fitting roughly 1,500 pages in one prompt.

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 GPT-5.4 Nano, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

→ Claude Haiku 5.5

Larger 1M tokens window fits more in one prompt.

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 cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work

→ GPT-5.4 Nano

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.

GPT-5.4 Nano: where it fits

OpenAI's cheapest GPT-5.4 variant at $0.20/$1.25 with a 400K window — a speed-and-cost tier for high-volume tasks, not deep reasoning. Released March 17, 2026 by OpenAI, it is built for cheapest GPT-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work, classification, extraction, ranking and sub-agent execution at scale, a 400K context in the smallest, fastest GPT-5.4 variant, and text and image input for cheap multimodal pipelines.

Its trade-offs: a nano tier — not built for hard reasoning or frontier coding, no published SWE-Bench Verified score (OpenAI reported SWE-Bench Pro instead), outclassed by GPT-5.4 and GPT-5.4 Mini whenever a task needs real depth, and image input only — no audio or video. At $0.2 in / $1.25 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

Claude Haiku 5.5 and GPT-5.4 Nano overlap enough that the right pick depends on your specific job. Claude Haiku 5.5 costs less per token; Claude Haiku 5.5 holds the larger context; and each leads in its own area — Claude Haiku 5.5 for 5x the context window of haiku 4.5 (1m vs 200k tokens) and double the max output (128k vs 64k), GPT-5.4 Nano for cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Claude Haiku 5.5 and GPT-5.4 Nano without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Claude Haiku 5.5 or GPT-5.4 Nano 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 GPT-5.4 Nano leans toward cheapest gpt-5.4-family tier at $0.20/$1.25 — built for high-volume, latency-sensitive work, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Haiku 5.5 or GPT-5.4 Nano?

Claude Haiku 5.5 is cheaper — $0.1/$0.5 per 1M tokens vs $0.2/$1.25 per 1M tokens, roughly 2× apart on input.

Which has the bigger context window?

Claude Haiku 5.5 — 1M tokens vs 400K, about 2.5× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Claude Haiku 5.5 and GPT-5.4 Nano together?

Yes — a multi-model platform like LumiChats gives you Claude Haiku 5.5, GPT-5.4 Nano and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Claude Haiku 5.5 or GPT-5.4 Nano?

Claude Haiku 5.5 — released October 7, 2026, about 7 months after GPT-5.4 Nano.

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.