API Key Validator
Validate and identify API key formats for major AI providers
API Key Input
⚠️ Your key is only processed locally in your browser - never sent to any server.
API Key Format Reference
| Provider | Prefix | Format |
|---|---|---|
| OpenAI | sk- | sk-{48 alphanumeric} |
| OpenAI (Project) | sk-proj- | sk-proj-{48+ chars} |
| OpenAI (Service) | sk-svcacct- | sk-svcacct-{48+ chars} |
| Anthropic | sk-ant- | sk-ant-{90+ chars} |
| Google (Gemini) | AIza | AIza{35 chars} |
| Cohere | (none) | {40 alphanumeric} |
| Hugging Face | hf_ | hf_{34 chars} |
| Mistral | (none) | {32 alphanumeric} |
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API Key Validator: Verify Key Formats Before Use
Debugging API authentication errors is frustrating. Often the issue is a malformed key — extra whitespace, wrong format, or paste errors. This validator checks your key against known formats for major AI providers.
Privacy: Your key never leaves your browser. All validation happens client-side.
Common API Key Issues
- Extra whitespace at beginning or end
- Newline characters from multi-line paste
- Quotes included from environment variable files
- Wrong prefix (e.g., using old OpenAI format)
- Truncated key (didn't copy full string)