SendGrid API Key Tester
Enter your SendGrid API key below and click 'Test Key' to check if it works. This tool will send a request to SendGrid asking, "Does this key work?" and return a response with an explanation.
🔑 How to Get Your API Key
2. Go to Settings > API Keys
3. Click 'Create API Key'
4. Choose 'Restricted Access' and select 'Mail Send' permissions
5. Copy the generated key (it won't be shown again)
6. Free tier: 100 emails/day
💻 Test in Terminal
This provider requires testing via command line for security reasons. This provider uses server-side authentication, so we'll test via terminal for better compatibility.
Use the command below to test your key:
curl -sS -X POST https://api.sendgrid.com/v3/mail/send -H 'Authorization: Bearer {{KEY}}' -H 'Content-Type: application/json' -d '{"personalizations":[{"to":[{"email":"test@example.com"}]}],"from":{"email":"test@example.com"},"subject":"Test Email","content":[{"type":"text/plain","value":"Hello world!"}]}'
💻 How to run this command in your terminal:
- Copy the command above by clicking the "Copy" button
- Open your terminal (Command Prompt on Windows, Terminal on Mac/Linux)
- Paste the command using Ctrl+V (Windows/Linux) or Cmd+V (Mac)
- Press Enter to execute the command
- Check the response - you'll see either a success message or an error explaining what's wrong
💡 Terminal Tips:
- Make sure you have
curlinstalled (it comes pre-installed on Mac and most Linux systems) - On Windows, you may need to install curl or use PowerShell's
Invoke-WebRequestinstead - If you see "command not found", try
curl --versionto check if it's installed
🔧 Common SendGrid API key errors
❌ 401
Cause: Invalid or revoked key.
Fix: Recreate the key at app.sendgrid.com with Mail Send access.
❌ 403
Cause: The key lacks Mail Send permission, or the sender isn't verified.
Fix: Give the key Mail Send scope and verify your sender identity.
🔑 API Key Format Guide
Your SendGrid API key should follow the correct format:
✅ Valid Format
SG.abc.def
Starts with "SG.". SendGrid keys start with SG. and contain two dot-separated segments.
❌ Invalid Format
invalid_key_format
Missing required prefix, wrong length, or incorrect format
How to check if your SendGrid API key is working
- Copy your key from app.sendgrid.com (Settings > API Keys).
- Paste it into the cURL command above and run it in your terminal.
- A 202 response means the key works; an error explains what's wrong.
❓ Frequently Asked Questions
How do I test my SendGrid API key?
Simply paste your API key into the form above and click "Test Key". Our tool will make a test request to SendGrid to verify your key works.
Is it safe to test my API key here?
Yes! All testing happens in your browser - we never see or store your API keys. The key never leaves your device.
What if my API key test fails?
Check the error message above. Common issues include invalid keys, expired keys, insufficient credits, or rate limiting. Use the troubleshooting guide above for specific solutions.
Can I test multiple API keys?
Yes, you can test as many keys as you need. Each test is independent and secure.
Why do I need to use the terminal?
Some providers use server-side authentication for enhanced security. The terminal method provides direct access to test your API key with full compatibility.
Use Cases
- Quickly verify if your SendGrid API key is valid
- Troubleshoot API key-related issues with detailed error messages
- Understand SendGrid API response codes and their meanings
- Validate email service credentials before sending campaigns
- Check email delivery permissions and quotas
Supported SendGrid Responses
This tool handles all SendGrid error codes, including:
- 200 (OK): Key is valid and working correctly
- 201 (Created): Request successful and resource created
- 202 (Accepted): Request accepted and being processed
- 400 (Bad Request): Invalid request format or parameters
- 401 (Unauthorized): The API key is incorrect or invalid
- 403 (Forbidden): API key lacks required permissions
- 404 (Not Found): Requested resource doesn't exist
- 429 (Rate Limit Exceeded): Too many requests in a short period
- 500 (Server Error): SendGrid servers are experiencing issues
Refer to the SendGrid Documentation for more details.