AI model comparison
Claude Haiku 4.5 vs o3
Pricing, context window, benchmarks, and features compared side by side. Or skip the guesswork and send one prompt to both.
Anthropic
Claude Haiku 4.5
Claude Haiku 4.5 is Anthropic’s fastest and most efficient model, delivering near-frontier intelligence at a fraction of the cost and latency of larger Claude models.
- Input / 1M
- $1
- Output / 1M
- $5
- Context
- 200K
OpenAI
o3
o3 is a well-rounded and powerful model across domains. It sets a new standard for math, science, coding, and visual reasoning tasks.
- Input / 1M
- $2
- Output / 1M
- $8
- Context
- 200K
At a glance
Quick verdict
How the two models stack up on the things people ask about most.
Lower price
Claude Haiku 4.5
1.8x cheaper for a typical chat
Higher intelligence score
o3
20.2 vs 16.9 on Artificial Analysis
Larger context window
Tie
200K vs 200K tokens
Newer release
Claude Haiku 4.5
Released October 15, 2025
Benchmarks
Benchmark scores
Independent scores from Artificial Analysis. Higher is better.
Intelligence index
Claude Haiku 4.516.9o320.2Coding index
Claude Haiku 4.543.9o3Not availableAgentic index
Claude Haiku 4.58o3Not availablePricing
Claude Haiku 4.5 vs o3 API pricing
Per-token API rates. Cheaper option highlighted.
| Metric | Claude Haiku 4.5 | o3 |
|---|---|---|
| Input tokensPer 1M tokens | $1 | $2 |
| Output tokensPer 1M tokens | $5 | $8 |
| Cached input (read)Per 1M tokens | $0.10 | $0.50 |
| Cache writePer 1M tokens | $1.25 | Not available |
| Web searchPer request | $0.01 | $0.01 |
What it costs in practice
Estimated cost per 1,000 requests at standard rates. Coding and long-document figures also show the cost when the input is already cached.
Chat message
2K in, 500 out
Claude Haiku 4.5$4.50o3$8Coding task
30K in, 4K out
Claude Haiku 4.5$50$23 cachedo3$92$47 cachedLong document summary
150K in, 2K out
Claude Haiku 4.5$160$25 cachedo3$316$91 cachedSpecs
Context window and capabilities
How much each model can read, how much it can write, and what it accepts as input.
| Metric | Claude Haiku 4.5 | o3 |
|---|---|---|
| Context window | 200K tokens | 200K tokens |
| Max output | 64K tokens | 100K tokens |
| Input types | File, Image, Text | File, Image, Text |
| Output types | Text | Text |
| Reasoning effort levels | Not available | Not available |
| Default reasoning effort | Not available | Not available |
| Release date | October 15, 2025 | April 16, 2025 |
Features
Supported features
API features available for each model.
| Metric | Claude Haiku 4.5 | o3 |
|---|---|---|
| Tool calling | Supported | Supported |
| Structured outputs | Supported | Supported |
| JSON mode | Supported | Supported |
| Reasoning | Supported | Supported |
| Temperature | Supported | Not supported |
| Stop sequences | Supported | Not supported |
| Deterministic seed | Not supported | Supported |
| Verbosity control | Not supported | Not supported |
Keep exploring
More on these models
Other head-to-heads, the full model page, and the alternatives list for each model.
Claude Haiku 4.5View full model details- Claude Haiku 4.5 vs Gemini 3.1 Flash Lite
- Claude Haiku 4.5 vs Gemini 2.5 Flash
- Claude Haiku 4.5 vs Claude Sonnet 4.5
- Claude Haiku 4.5 vs Gemini 2.5 Pro
- Claude Haiku 4.5 vs GLM 4.6
- Claude Haiku 4.5 vs Claude Sonnet 4
- Claude Haiku 4.5 vs Qwen3.5-122B-A10B
- Claude Haiku 4.5 vs o4 Mini
- Claude Haiku 4.5 vs Kimi K2 0905
- Claude Haiku 4.5 vs o1
- Claude Haiku 4.5 vs Mistral Medium 3.5
- Claude Haiku 4.5 vs Command A
- Claude Haiku 4.5 vs o3 Mini
- Claude Haiku 4.5 vs Sonar Reasoning Pro
Our take
Claude Haiku 4.5 is 1.8x cheaper for a typical chat. o3 scores higher on the Artificial Analysis Intelligence Index (20.2 vs 16.9). The right pick depends on your workload, so the quickest way to settle it is to send the same prompt to both and compare.
FAQ
Frequently asked questions
Is Claude Haiku 4.5 or o3 cheaper?
Claude Haiku 4.5 is cheaper for a typical chat (2K input tokens and 500 output tokens). Claude Haiku 4.5 costs $1 per 1M input tokens and $5 per 1M output tokens, while o3 costs $2 per 1M input tokens and $8 per 1M output tokens.
Which has a bigger context window, Claude Haiku 4.5 or o3?
Claude Haiku 4.5 supports up to 200K tokens of context, compared with 200K for o3.
Is Claude Haiku 4.5 smarter than o3?
On the Artificial Analysis Intelligence Index, Claude Haiku 4.5 scores 16.9 and o3 scores 20.2, putting o3 ahead. Benchmarks don't capture everything, so the best test is running your own prompts through both.
Can I use Claude Haiku 4.5 and o3 at the same time?
Yes. Shortcut Chat sends one prompt to multiple models at once, so you can see Claude Haiku 4.5 and o3 answer side by side and keep the better response.
Why choose? Ask both.
Send one prompt to Claude Haiku 4.5 and o3 at the same time. Compare the answers side by side and keep the best one.