AI model comparison

Claude Haiku 4.5 vs GPT-5 mini

Comparing two fast, lower-cost models for high-volume classification, routing, and lightweight extraction where latency and unit price matter most.

Pricing & context

All figures below are list prices pulled directly from the Harpd pricing registry (last verified 2026-08-18). Prices change often — open each model’s source link to confirm before budgeting.

MetricClaude Haiku 4.5GPT-5 mini
ProviderAnthropicOpenAI
Input / 1M tokens$1$0.25
Output / 1M tokens$5$2
Cached input / 1M tokens$0.1$0.03
Batch discount50% off50% off
Context window200,000 tokens400,000 tokens
SourceAnthropic pricing ↗OpenAI pricing ↗
Claude Haiku 4.5

Capabilities

Claude Haiku 4.5 is positioned as a fast, cost-efficient model with strong performance for its tier, a 200k context window, and prompt caching.

GPT-5 mini

Capabilities

GPT-5 mini is a small, low-latency model with a 400k context window, prompt caching, and a very low per-token price aimed at high-volume calls.

Recommendation

Both are designed for cheap, high-throughput work, so the pragmatic move is to benchmark each on your highest-volume path. Claude Haiku 4.5 tends to be chosen where output quality at the small tier matters; GPT-5 mini’s lower price suits pure volume. Neither is universally “better” — test both on your real traffic before standardizing.

Updated 2026-08-18.

Answer

Price tells you what a model costs. It does not tell you whether it can replace your current model on your real tasks.

Evidence
  • Benchmarks measured on Harpd are planned — see /benchmarks/.

Frequently asked questions

How do I know if a cheaper model is safe to use?
Price only tells you cost, not whether a model preserves your quality bar on real work. The safe path is to run a representative sample of your actual tasks through both models and compare outputs against your acceptance criteria. Harpd’s ModelSwitch does exactly this — it switches only once a cheaper model passes your tasks, not on price alone.
Is price a good proxy for quality?
No. List price reflects positioning and context length, not how a model performs on your specific workload. A cheaper model can be better for narrow tasks and worse for others. Treat price as one input to a cost-vs-capability decision, and validate capability with real-task testing rather than assuming a ranking.
What is cost per successful task?
Cost per successful task divides your total spend by the tasks that actually succeeded, folding in retries and failures that still cost tokens. A model with a lower per-token price can end up more expensive per successful task if it fails or retries more often. See /cost-per-successful-task/ for the full method.
How does ModelSwitch test a replacement model?
ModelSwitch runs your real tasks against a candidate model and compares results to your current one using your defined acceptance checks. It switches only when the cheaper model passes, and reports the measured savings. It does not rely on published benchmarks or price as a proxy for quality.