Head-to-head
GPT-5.2 vs Claude Haiku 4.5: which AI model wins in 2026?
GPT-5.2 ($14/1M out) and Claude Haiku 4.5 ($5/1M out) are two of the most-used AI models in 2026. Across 4 community votes, Claude Haiku 4.5 leads with 67% approval.
Quick verdict
On Reasoning, pick GPT-5.2: the arena rates it 4/5 against 3/5 for Claude Haiku 4.5. On budget, Claude Haiku 4.5 wins: it starts at $5/1M out versus $14/1M out for GPT-5.2.
Line-by-line comparison
Strengths and weaknesses
GPT-5.2
- 80.0% SWE-bench Verified and 55.6% SWE-Bench Pro at launch, near parity with Claude Opus 4.5 (80.9%)
- GDPval: ties or beats human professionals in 70.9% of comparisons, nearly double GPT-5.1's 38.8%
- Strong science and math: 92.4% GPQA Diamond (Thinking, 93.2% Pro) and 40.3% FrontierMath, state of the art at release
- 400K context with near-perfect MRCR v2 long-context retrieval up to 256K tokens
- 30% fewer hallucinations than GPT-5.1 (error rate on real ChatGPT queries down from 8.8% to 6.2%)
- Cheaper than its successors: $1.75/$14 per 1M vs $2.50/$15 (GPT-5.4) and $5/$30 (GPT-5.5)
- Speed is the top community complaint: extended thinking reported as low as ~4 tokens/s in ChatGPT, and Pro can think for a very long time and still fail
- Headline benchmark scores were obtained at xhigh reasoning effort, which consumes far more tokens and time than default settings
- Widely criticized personality regression vs GPT-5.1: Reddit users called it 'too corporate, too safe' and 'a step backwards' for chat and writing
- Coding lags Anthropic's line in head-to-head Elo comparisons (a later Opus 4.7 analysis cited a 144 Elo gap); no audio modality, no fine-tuning
- Already superseded as of mid-2026: OpenAI recommends GPT-5.5 and GPT-5.2 no longer appears on the main API pricing page
Claude Haiku 4.5
- 73.3% on SWE-bench Verified, about 90% of Sonnet 4.5's agentic coding at one third of the price
- Fast: more than 2x Sonnet 4 speed per Anthropic, with launch customers reporting 4-5x faster than Sonnet 4.5; ~92-110 output tok/s measured by Artificial Analysis
- Devs report precise, localized code edits that avoid touching irrelevant code, better than GPT-5 mini class in early testing
- Supports both vision input and extended thinking, rare at this price tier at launch
- Well suited as worker model in multi-agent setups (Sonnet/Opus plans, parallel Haiku sub-agents execute)
- Prompt caching reads at $0.10/1M and 50% Batch API discount cut effective cost further
- $5/1M output is pricey for a small model: Gemini Flash and GPT mini tiers undercut it several-fold on output-heavy tasks
- 200K context (vs 1M for Sonnet 5/Opus siblings) and 64K max output limit large-codebase and long-output work
- Mediocre cross-domain reasoning: users report weak results on GPQA, MedQA, MMMU style knowledge tasks
- Throughput varies widely in practice (82-208 tok/s reported) and quality degrades on long 7-8+ minute agentic sessions
- Knowledge cutoff (reliable to Feb 2025) is dated by mid-2026 standards
Cast your verdict
One recommendation per tool per gladiator. It reshapes the crowd score everyone sees.
The arena’s verdict on GPT-5.2
Pick GPT-5.2 over GPT-5.1 for heavy reasoning, long-context, or agentic work: it nearly doubles GPT-5.1's GDPval win rate, cuts hallucinations 30%, and handles 400K contexts reliably. In mid-2026 it is mainly a value play, priced at $1.75/$14 versus $5/$30 for GPT-5.5 while staying competent on most professional tasks. Avoid it for latency-sensitive chat and creative writing, where users found it slow and flatter than GPT-5.1. Teams that want OpenAI's current frontier should pay up for GPT-5.5 instead.
The arena’s verdict on Claude Haiku 4.5
Pick Haiku 4.5 if you are on the Anthropic stack and need near-Sonnet coding quality at low latency and a third of the price: it is a massive step up from Haiku 3.5 and excels as the worker model in multi-agent pipelines. It remains Anthropic's current small model as of July 2026, so it is the default cheap tier for Claude-based products. Avoid it for deep cross-domain reasoning, very large codebases (200K context cap), or pure cost-per-token shopping, where Gemini Flash and GPT mini tiers are now cheaper, and step up to Sonnet 5 when quality matters more than speed.
What the crowd says
On GPT-5.2
“The thinking speed is brutal, I clocked something like 4 tok/s in ChatGPT on extended thinking. Pro will grind for ages and still whiff. Great scores, painful to actually use.”
“GDPval numbers are wild, it ties or beats human pros in 71% of comparisons. For science and math work (92.4 GPQA Diamond) it earned a spot in my stack.”
On Claude Haiku 4.5
“The precise localized edits are the underrated feature. It fixes the line that needs fixing and leaves the rest alone. GPT mini class models keep rewriting half my file.”
“Haiku 4.5 gives me about 90% of Sonnet agentic coding at a third of the price, and it is fast enough that edit loops feel instant. My default for quick fixes now.”
Keep comparing
Frequently asked questions
Is GPT-5.2 better than Claude Haiku 4.5?
The crowd currently sides with Claude Haiku 4.5: 67% recommend it, versus 50% for GPT-5.2 (4 votes). On Reasoning, GPT-5.2 rates higher (4/5 vs 3/5). The right pick depends on your use case. The line-by-line comparison on this page breaks down pricing, key specs and arena ratings.
Which is cheaper, GPT-5.2 or Claude Haiku 4.5?
Claude Haiku 4.5 is cheaper: it starts at $5/1M out, while GPT-5.2 starts at $14/1M out.
How much do GPT-5.2 and Claude Haiku 4.5 cost per 1M tokens?
GPT-5.2: $1.75/1M in per 1M input tokens, $14/1M out per 1M output tokens. Claude Haiku 4.5: $1/1M in per 1M input tokens, $5/1M out per 1M output tokens.