Compare Costs

GPT-4o vs Claude 3.5 Sonnet: Token Cost & Efficiency Comparison

When choosing between OpenAI's GPT-4o and Anthropic's Claude 3.5 Sonnet, developers look at benchmark accuracy. However, tokenization efficiency and API pricing skew the true operating costs. This comparative analysis breaks down token pricing and tokenizer compression ratios.

Run the Calculations Locally

Test your operational cost parameters on the interactive dashboard.

Launch the AI Token Calculator

1. API Pricing Models Compared

GPT-4o is priced at $2.50 per million input tokens and $10.00 per million output tokens. Claude 3.5 Sonnet is priced at $3.00 per million input tokens and $15.00 per million output tokens. On pricing alone, OpenAI starts with a 16% input and 33% output cost advantage.

2. Tokenizer Compression Efficiency (o200k vs. Claude Tiktoken)

GPT-4o utilizes the `o200k_base` tokenizer with a 200k vocabulary, compressing English and non-English text highly. Claude uses a tokenizer with a smaller vocabulary. In tests, GPT-4o compresses standard text 10-15% better than Claude, requiring fewer tokens to send the same prompt volume.

3. Prompt Caching Differences

Both providers offer prompt caching. Anthropic Claude charges a 25% premium to write the cache, but offers a 90% discount on cache-reads. OpenAI GPT-4o offers a flat 50% discount on cached input tokens. For long-running sessions, Claude's cache-read discount can overcome its higher base price.

Frequently Asked Questions

Which is cheaper, GPT-4o or Claude 3.5 Sonnet?

GPT-4o is cheaper for standard requests due to its lower base token price and superior token compression. However, for massive, highly repetitive prompts, Claude can be cheaper due to its 90% prompt caching discount.

Does tokenizer efficiency impact latency?

Yes. Since GPT-4o compresses text into fewer tokens, it processes and generates requests slightly faster because the model performs fewer total inference steps.