GPT-4o mini vs Claude Haiku 4.5: token pricing & cost compared (July 2026)

Is GPT-4o mini cheaper than Claude Haiku 4.5?

It depends on your token ratio. GPT-4o mini is priced at $0.15 per million input tokens and $0.60 per million output tokens via OpenRouter. Claude Haiku 4.5 is in a similar band. Plug your actual avg input/output tokens per call into the calculator above to get an exact monthly figure for your usage.

Which model is better for RAG and document processing?

RAG pipelines are input-heavy — you're stuffing context windows with retrieved chunks and getting short structured responses back. Compare input token prices first, then factor in context window limits. Claude Haiku 4.5's 200K context window can reduce the number of chunked calls needed on long documents, which may offset a higher per-token price.

Can I use Claude Haiku 4.5 as a drop-in for GPT-4o mini?

For most classification, routing, and summarisation tasks — yes, with prompt adjustments. Anthropic models respond better to explicit XML-tagged system prompts (e.g. <task>, <context>). For function calling and JSON output, both models perform comparably. Expect a 1–2 day prompt-tuning pass to fully leverage Haiku 4.5.

What's the context window difference?

GPT-4o mini supports up to 128K context tokens. Claude Haiku 4.5 supports up to 200K. For very long documents, Haiku 4.5's larger window can eliminate chunking entirely — which reduces call count, latency, and often total cost even at a similar per-token price.

Which model has lower latency?

Both are optimised for low-latency inference. GPT-4o mini benefits from OpenAI's globally distributed infrastructure. Claude Haiku 4.5 is Anthropic's fastest tier. Actual latency depends on region, prompt size, and time of day — benchmark both with your specific prompt template before committing.