API Key Format Validator

Validate API key formats — never contacts any API

🔒 Files never leave your browser
Privacy Note: This tool only checks the format of API keys using regex patterns. It never contacts any external API or server. Your keys stay in your browser.

How to Use API Key Format Validator

Select provider

Choose the API provider or use auto-detect.

Paste key

Paste your API key (stays in your browser).

Validate

See if the format matches the expected pattern.

Why Choose AllTools API Key Format Validator?

  • ✓ 18+ providers
  • ✓ Auto-detect
  • ✓ Regex format check
  • ✓ Length validation
  • ✓ Prefix check
  • ✓ Never phones home

Why Use This Tool

  • ★ Quickly verify you copied the right key format
  • ★ Auto-detects 18+ provider formats
  • ★ Your API key never leaves your browser
  • ★ No sign-up required — format check only

API Key Format Patterns

Each API provider uses a distinct key format: OpenAI keys start with sk- (~51 chars), Stripe live keys start with sk_live_, AWS access keys start with AKIA (exactly 20 chars), GitHub PATs start with ghp_ (40 chars). Knowing the expected format helps you quickly verify you have the right key before debugging authentication errors. This tool checks format only — it never makes any network requests.

Related Resources

Check password strength → Decode JWT tokens → Generate hashes →

Frequently Asked Questions

Does this test if my key is active? ▼
No. This only checks the format (prefix, length, character set). It never contacts any API or server. Your key stays in your browser.
Is it safe to paste my API key? ▼
Yes. The key never leaves your browser. No network requests are made. This is a format-only check using regex patterns.
Which API providers are supported? ▼
OpenAI, Stripe, AWS, GitHub, Anthropic, Google Cloud, Azure, Twilio, SendGrid, Mailgun, and more — over 18 providers.

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