The pricing landscape in 2025
AI API pricing has dropped dramatically over the past two years, and the gap between leading models has narrowed. Both Anthropic and OpenAI now offer tiered lineups — a frontier model, a mid-tier workhorse, and a fast/cheap option — so the right answer depends heavily on the task, not just the brand.
Let's compare the mid-tier models that most production apps actually use: Claude Sonnet 4 and GPT-4o.
Let's compare the mid-tier models that most production apps actually use: Claude Sonnet 4 and GPT-4o.
Head-to-head price table
Claude Sonnet 4: $3.00 input / $15.00 output per million tokens.
GPT-4o (2024-11-20): $2.50 input / $10.00 output per million tokens.
At face value, GPT-4o is cheaper — about 17% cheaper on input and 33% cheaper on output. But price per token isn't the whole story.
At face value, GPT-4o is cheaper — about 17% cheaper on input and 33% cheaper on output. But price per token isn't the whole story.
Efficiency: tokens used per task
Claude models tend to produce more concise outputs for the same task. In internal benchmarks and community reports, Claude Sonnet 4 often generates 10–20% fewer output tokens than GPT-4o for equivalent answers. Fewer output tokens directly cuts your bill.
If GPT-4o generates 250 tokens and Claude generates 210 tokens for the same answer, the effective cost difference shrinks significantly — and can even flip in Claude's favor for output-heavy workloads.
If GPT-4o generates 250 tokens and Claude generates 210 tokens for the same answer, the effective cost difference shrinks significantly — and can even flip in Claude's favor for output-heavy workloads.
Context window and caching
Both models offer 200K token context windows. However, Anthropic offers prompt caching at $0.30/M tokens (a 90% discount on repeated context), which is a significant advantage for apps with large system prompts or documents that repeat across calls. OpenAI also offers caching but at higher effective prices.
For applications with a 10,000-token system prompt that runs 10,000 times per day, caching alone can save thousands of dollars monthly.
For applications with a 10,000-token system prompt that runs 10,000 times per day, caching alone can save thousands of dollars monthly.
Which model is cheaper for your use case?
Chatbots and customer support: GPT-4o has a slight edge on raw price, but if your system prompt is large and reused, Claude's caching makes it competitive.
Long-document analysis: Claude's extended thinking and efficient summarization often produce fewer output tokens, making it cost-competitive despite higher list prices.
Code generation: GPT-4o tends to be slightly more verbose. For short code snippets, prices are nearly equivalent. For large codebases, Claude's conciseness adds up.
High-volume classification or extraction: Consider GPT-4o Mini ($0.15/$0.60) or Claude Haiku 4.5 ($0.80/$4.00). Both are dramatically cheaper than the mid-tier models for simple tasks.
Long-document analysis: Claude's extended thinking and efficient summarization often produce fewer output tokens, making it cost-competitive despite higher list prices.
Code generation: GPT-4o tends to be slightly more verbose. For short code snippets, prices are nearly equivalent. For large codebases, Claude's conciseness adds up.
High-volume classification or extraction: Consider GPT-4o Mini ($0.15/$0.60) or Claude Haiku 4.5 ($0.80/$4.00). Both are dramatically cheaper than the mid-tier models for simple tasks.
The hidden cost: reliability and retries
Price per token only matters if the model produces correct output on the first try. A cheaper model that requires 2–3 retries or human review is more expensive in practice. Factor in your quality requirements and expected retry rates when comparing total cost of ownership.
Bottom line
GPT-4o wins on list price. Claude Sonnet 4 is more competitive once you account for output efficiency and prompt caching. For most production workloads, the real-world cost difference is under 20% — well within the margin where quality, latency, and API reliability should drive the decision.
Use the TokenRate calculator to plug in your actual prompt and expected response lengths to get a precise comparison for your specific use case.
Use the TokenRate calculator to plug in your actual prompt and expected response lengths to get a precise comparison for your specific use case.