Claude Haiku 5.5 vs GPT-5.6 Terra

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-5.6 Terra for balanced everyday work at roughly half of sol's price or competitive with gpt-5.5 quality at about 2x lower cost. On a tight budget at scale, Claude Haiku 5.5 is the value pick.

Claude Haiku 5.5 (Anthropic) and GPT-5.6 Terra (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-5.6 Terra is the mid-tier daily driver of the GPT-5.6 family — near-flagship quality at about half of Sol's cost. Their biggest split is price, and the breakdown below shows exactly how that plays out for your workload.

Key differences at a glance

Side-by-side specs

SpecClaude Haiku 5.5GPT-5.6 Terra
ProviderAnthropic (US) OpenAI (US)
ReleasedOctober 7, 2026 July 9, 2026
Context window1M tokens (~1,500 pages) 1M (~1,500 pages)
Price (in/out)$0.1/$0.5 per 1M tokens $2.5/$15 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

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.

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-5.6 Terra ($2.5/$15 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 is the newer of the two.

Balanced everyday work at roughly half of Sol's price

GPT-5.6 Terra

Claude Haiku 5.5 is comparatively weak here — pricing jumps roughly 5x beyond 100K-token prompts ($0.50/$2.50 per million vs the headline $0.10/$0.50)

Competitive with GPT-5.5 quality at about 2x lower cost

GPT-5.6 Terra

GPT-5.6 Terra lists competitive with GPT-5.5 quality at about 2x lower cost among its strengths; Claude Haiku 5.5 does not.

Solid agentic coding (Terminal-Bench 2.1 in the mid-80s)

GPT-5.6 Terra

GPT-5.6 Terra lists solid agentic coding (Terminal-Bench 2.1 in the mid-80s) 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 GPT-5.6 Terra, 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 balanced everyday work at roughly half of sol's price

→ GPT-5.6 Terra

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-5.6 Terra: where it fits

The mid-tier daily driver of the GPT-5.6 family — near-flagship quality at about half of Sol's cost. Released July 9, 2026 by OpenAI, it is built for balanced everyday work at roughly half of Sol's price, competitive with GPT-5.5 quality at about 2x lower cost, solid agentic coding (Terminal-Bench 2.1 in the mid-80s), and same 1M context and programmatic tool calling as Sol.

Its trade-offs: fewer independently verified benchmarks than Sol, and trails it across coding evals, and no open weights. At $2.5 in / $15 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

Claude Haiku 5.5 and GPT-5.6 Terra overlap enough that the right pick depends on your specific job. Claude Haiku 5.5 costs less per token; 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-5.6 Terra for balanced everyday work at roughly half of sol's price. 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-5.6 Terra 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-5.6 Terra 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-5.6 Terra leans toward balanced everyday work at roughly half of sol's price, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Haiku 5.5 or GPT-5.6 Terra?

Claude Haiku 5.5 is cheaper — $0.1/$0.5 per 1M tokens vs $2.5/$15 per 1M tokens, roughly 25× 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.

Can I use both Claude Haiku 5.5 and GPT-5.6 Terra together?

Yes — a multi-model platform like LumiChats gives you Claude Haiku 5.5, GPT-5.6 Terra 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-5.6 Terra?

Claude Haiku 5.5 — released October 7, 2026, about 3 months after GPT-5.6 Terra.

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.