Claude 3.5 Haiku latest vs o3-mini
Claude 3.5 Haiku latest (Anthropic, 200,000-token context) versus o3-mini (Azure OpenAI, 200,000-token context). o3-mini is cheaper by 8% on a blended token mix. Claude 3.5 Haiku latest uniquely supports function calling and vision input. o3-mini uniquely supports native reasoning mode. Across 3 public benchmarks we tracked, Claude 3.5 Haiku latest wins 0 and o3-mini wins 3. Use the live calculator below to plug your real usage shape into both, then route the winner via Agent Command Center for shadow A/B without code changes.
Bottom line — Claude 3.5 Haiku latest vs o3-mini
Claude 3.5 Haiku latest and o3-mini are priced within 8% of each other, so cost alone is not the deciding factor. The comparison comes down to capabilities, context window, and benchmark performance on the specific task shape your workload demands.
On capability surface area, the models diverge: Claude 3.5 Haiku latest supports function calling where the other does not; Claude 3.5 Haiku latest supports vision input where the other does not; Claude 3.5 Haiku latest supports pdf input where the other does not. These differences are binary — either your workload needs the capability or it does not. Check whether any critical path in your agent pipeline depends on a capability only one model provides before committing to a migration.
Across 3 public benchmarks, Claude 3.5 Haiku latest leads on 0 and o3-mini leads on 3. The widest gap is on gpqa-diamond, where o3-mini scores 35.4 points higher. Benchmarks are noisy and task-dependent — a model that leads on arena-elo may trail on code generation. The safest approach is to run both models on your own golden set before treating any benchmark as decisive.
For teams evaluating both models, the recommended path is a shadow A/B test: route production traffic through an OpenAI-compatible gateway, mirror a percentage to the candidate model, score both responses with an automated evaluator (faithfulness, tool-call correctness, latency), and compare cohort-level metrics over two weeks. Future AGI Agent Command Center supports this pattern with a single `base_url` change and built-in evaluators from the ai-evaluation SDK.
Live workload comparison
Same workload run through both models. The cheaper one is highlighted.
strategy: cost-optimized
primary:
model: claude-3-5-haiku-latest
provider: anthropic
fallback:
model: o3-mini
provider: azure-openai
shadow: { sample_rate: 0.05 } # mirror 5% of traffic to compare quality live| Claude 3.5 Haiku latest | o3-mini | |
|---|---|---|
| Input price | $1.00/M | $1.10/M |
| Output price | $5.00/M | $4.40/M |
| Context window | 200,000 | 200,000 |
| Max output | 8,192 | 100,000 |
| Function calling | ✓ | — |
| Vision | ✓ | — |
| Audio input | — | — |
| Reasoning | — | ✓ |
| Prompt caching | ✓ | ✓ |
| Structured output | ✓ | ✓ |
| Pricing verified | May 7, 2026 | Aug 6, 2026 |
Benchmark comparison
Side-by-side public benchmark scores. Greener bar = winner.
Cost at scale: monthly spend at three usage volumes
Estimated monthly cost assuming 1,000 input + 200 output tokens per request — a realistic chat-agent shape. Adjust your own usage in the calculator at the top of this page for an exact number.
| Scale | Claude 3.5 Haiku latest | o3-mini | Delta |
|---|---|---|---|
| Startup 10K requests/day | $600 /mo | $594 /mo | $6.00/mo |
| Mid-market 100K requests/day | $6,000 /mo | $5,940 /mo | $60.00/mo |
| Enterprise 1M requests/day | $60,000 /mo | $59,400 /mo | $600/mo |
At enterprise scale (1M requests/day), a difference of even ~10% in unit price compounds into thousands of dollars per month. Cached input pricing and batch tiers can shift this further — both are surfaced on each model's own page.
When to choose which
Picked from the data above — not vendor marketing. Match the rules to your workload, not the other way around.
Your inputs include screenshots, diagrams, or product photos — Claude 3.5 Haiku latest accepts image input natively, the other doesn't.
Your tasks involve multi-step planning or math-heavy reasoning — o3-mini ships a native reasoning mode that explicitly thinks before responding, the other doesn't.
Your agent calls tools or APIs — Claude 3.5 Haiku latest supports function calling natively, the other model needs a parser shim.
On gpqa-diamond, o3-mini scores 35.4 points higher — if your workload pattern matches that benchmark's task shape, the gap is meaningful.
Capability diff — what you gain and lose on the swap
A specific list of what each model has that the other doesn't. If your workload depends on a row in Only Claude 3.5 Haiku latest, switching to o3-mini means re-architecting that path (and vice versa).
- • Function calling
- • Vision input
- • PDF input
- • Native reasoning mode
Capabilities both share (3)
- ✓ Streaming
- ✓ Structured output (JSON schema)
- ✓ Prompt caching
Benchmark winners — by the numbers
For each public benchmark that has scores for both models, the higher score and the size of the gap. Benchmarks are noisy — treat anything under a 2-point delta as effectively tied.
| Benchmark | Claude 3.5 Haiku latest | o3-mini | Winner | Δ |
|---|---|---|---|---|
| gpqa-diamond | 41.6 | 77.0 | o3-mini | +35.4 |
| humaneval | 88.1 | 89.0 | o3-mini | ~0 |
| mmlu-pro | 65.0 | 79.7 | o3-mini | +14.7 |
Migration considerations
Concrete differences to wire through your stack before you flip traffic from one to the other.
- Max output tokens differ: 8,192 on Claude 3.5 Haiku latest vs 100,000 on o3-mini. Long-form generation tasks may truncate differently — adjust streaming UI and chunking accordingly.
- Claude 3.5 Haiku latest has capabilities o3-mini lacks: Function calling, Vision input, PDF input. Switching to o3-mini means re-architecting any flow that depends on these.
- o3-mini has capabilities Claude 3.5 Haiku latest lacks: Native reasoning mode. Worth wiring through the agent design before commit.
- Provider changes from Anthropic to Azure OpenAI. API authentication, rate-limit policy, regional availability, and billing all shift. Most teams route through an OpenAI-compatible gateway (e.g., Future AGI Agent Command Center) so the swap is a single `base_url` change instead of an SDK rewrite.
- Pricing on Claude 3.5 Haiku latest was last verified 133 days ago — confirm against the provider's published rate card before committing to a multi-month migration.
How to A/B test Claude 3.5 Haiku latest vs o3-mini in production
If you're stuck between the two, run them side-by-side on real traffic. Four steps the Future AGI team uses internally:
- 1. Point your existing OpenAI SDK at
https://gateway.futureagi.com/v1. No code change beyondbase_urland a virtual key. - 2. Mark Claude 3.5 Haiku latest primary, mirror 20% of traffic to o3-mini in shadow mode. Both responses are logged; only the primary is served to users.
- 3. Score every shadow response with an evaluator — faithfulness, tool-call correctness, response latency, cost. Built-in evaluators in ai-evaluation cover the common axes.
- 4. Compare cohort-level metrics after two weeks. Switch primary when the candidate wins on what matters to your workload — and stays within your latency budget.
Full walkthrough on the Agent Command Center page.
FAQ — Claude 3.5 Haiku latest vs o3-mini
Which is cheaper, Claude 3.5 Haiku latest or o3-mini? ▾
o3-mini is cheaper by roughly 8% on a blended input + output token mix. Input prices are $1.00/M for Claude 3.5 Haiku latest versus $1.10/M for o3-mini; output prices are $5.00/M versus $4.40/M. The exact savings depend on your input:output ratio — use the live calculator above to plug in your own request shape.
What is the context window of Claude 3.5 Haiku latest versus o3-mini? ▾
Claude 3.5 Haiku latest supports up to 200,000 tokens of context. o3-mini supports up to 200,000 tokens. o3-mini has the larger window by a factor of 1.0x, which matters for long-document RAG, multi-turn agent sessions, and tasks that need to keep an entire codebase in working memory.
Do Claude 3.5 Haiku latest and o3-mini both support tool calling? ▾
Only Claude 3.5 Haiku latest supports native function calling. The other model can still be made to call tools through a structured-output workaround, but the reliability of that pattern is lower than native support.
Can Claude 3.5 Haiku latest and o3-mini process images? ▾
Claude 3.5 Haiku latest accepts native image input. o3-mini does not — you would need to route image-heavy workloads through Claude 3.5 Haiku latest or add a separate vision model in front of o3-mini.
Which model supports prompt caching for cost reduction? ▾
Both Claude 3.5 Haiku latest and o3-mini support prompt caching. Cached input tokens are typically discounted 50–90% versus uncached input, depending on the provider. For agents with a stable system prompt + retrieval context, the cached pricing tier is the real unit economics number to track.
When should I choose Claude 3.5 Haiku latest over o3-mini? ▾
Your inputs include screenshots, diagrams, or product photos — Claude 3.5 Haiku latest accepts image input natively, the other doesn't. Your agent calls tools or APIs — Claude 3.5 Haiku latest supports function calling natively, the other model needs a parser shim.
When should I choose o3-mini over Claude 3.5 Haiku latest? ▾
Your tasks involve multi-step planning or math-heavy reasoning — o3-mini ships a native reasoning mode that explicitly thinks before responding, the other doesn't. On gpqa-diamond, o3-mini scores 35.4 points higher — if your workload pattern matches that benchmark's task shape, the gap is meaningful.
How do I A/B test Claude 3.5 Haiku latest against o3-mini in production? ▾
Route both through an OpenAI-compatible gateway like Future AGI Agent Command Center with shadow mode enabled. Send 100% of traffic to your primary model, mirror 10–20% to the candidate, score every response with an evaluator (faithfulness, tool-call correctness, response time), and compare cohort-level metrics for two weeks. Switch when the candidate wins on the metrics that matter to your workload and stays within your latency budget.