Anthropic API Key Checker: Verify Claude Model Authenticity
How to check if your Anthropic API key actually connects to Claude — or if you are being served a cheaper model.
Anthropic's Claude models are among the most popular targets for API fraud. Providers claim to offer Claude 3.5 Sonnet or Claude 3 Opus, but secretly substitute them with cheaper alternatives. Here is how to detect it.
Common Anthropic API Scams
- Claude Haiku sold as Sonnet/Opus — 10x cheaper model, same API format
- OpenAI models disguised as Claude — GPT-3.5 with system prompt pretending to be Claude
- Token count manipulation — Reported usage 2-3x actual consumption
- Relay server interception — Your data passes through unauthorized middlemen
How to Verify Your Anthropic Key
Paste your Anthropic API key (starts with sk-ant-) into API-DNA and get an instant report showing:
- Whether the key connects directly to Anthropic or through a relay
- The actual model family detected via behavioral fingerprinting
- Token count accuracy — reported vs estimated consumption
- Infrastructure details — server location, ASN, response headers