How to Get a NeverBounce API Key

Before you start

Smart Email Verifier doesn’t sell verification credits. It sends each address to the provider you pick, using your own NeverBounce API key. NeverBounce bills you for the checks, and the extension sets the daily limit (50 a day free, 500 a day on Premium).

You need two things:

• A NeverBounce account. Sign up at app.neverbounce.com/register. New accounts get a small batch of free credits, which is enough to test the setup.
• The extension installed and pinned. If you haven’t done that yet, follow Getting Started first.

Tip: Accounts without a payment method are rate-limited on the API. That’s fine for a test, but checks will slow down on longer lists. Add a card in NeverBounce billing before you verify a real list.

Create your NeverBounce API key

NeverBounce doesn’t hand you one master key. Instead, you create an “app” for each tool that connects to your account, and each app gets its own key. That way you can revoke the extension’s key without breaking anything else.

1. Sign in to the NeverBounce dashboard.
2. Open Apps from the top menu.
3. Create a Custom Integration. Choose the custom integration option, then name it something you’ll recognise later, such as Smart Email Verifier.
4. Copy the API key. NeverBounce shows the key on the app’s page. Copy all of it, with no spaces at either end.

Note: NeverBounce sometimes renames menu items. If you can’t find Apps, search their help centre for “custom integration”. The NeverBounce API docs cover the same steps.

Add the key to Smart Email Verifier

1. Open the extension from the Chrome toolbar and click the Settings tab.
2. Find the NeverBounce card and paste your key into the API key field.
3. Click Save. You’ll see a short “Saved!” message, and the key switches to a masked preview (the first four and last three characters).
4. Click Test Connection. If the key works you’ll see Connected successfully. The test reads your account info and doesn’t spend a credit.
5. Optional: make NeverBounce your default. Under Default Provider at the top of Settings, pick NeverBounce, and the Verify tab will use it automatically.

Your key is stored in Chrome’s local storage on this device only. Makeinfo never receives it. Requests go straight from your browser to api.neverbounce.com.

Now go to the Verify tab. Type one address you know is real and click Verify. A green Valid badge means everything is working.

What a NeverBounce check costs

Each address you verify uses one NeverBounce credit. Duplicates in a list are checked (and charged) every time they appear, so remove them first.

NeverBounce sells credits in pay-as-you-go packs, and the price per check drops as packs get bigger. At small volumes it’s roughly $8 per 1,000 checks. Prices change, so check the NeverBounce pricing page before you buy.

Two limits apply at the same time, and they work independently:

• Your NeverBounce credit balance. When it hits zero, NeverBounce stops answering and results come back as Unknown.
• The extension’s daily limit. 50 checks a day on Free, 500 on Premium. It resets at midnight UTC.

Not sure NeverBounce is the right fit? See Which provider should I use?

Troubleshooting

Test Connection shows an error

The message comes straight from NeverBounce. The usual causes:

• The key was copied with a space, or only partly. Copy it again from the app’s page and click Save.
• The app was deleted or its key regenerated in NeverBounce. Create a new key and paste it in.
• A message like “HTTP 4xx”. The request reached NeverBounce but was rejected. Check that the account is active and not suspended.

Every result comes back as Unknown

This almost always means the credits have run out. Check your balance in the NeverBounce dashboard. If you still have credits, try one address you know is good. A single Unknown is normal for strict mail servers. See result statuses for what each status means.

Checks are slow

Accounts with no payment method on file are rate-limited by NeverBounce. Add a card in billing to lift the limit.

Still stuck? Email [email protected] and tell us the exact error message (never send the API key itself).