---
title: Get started with the Developers page
slug: get-started-with-the-developers-page
createdAt: 2026-11-10T05:22:05.572Z
---

The **Developers** page in your [mailfloss dashboard](https://app.mailfloss.com/api) brings together API keys, webhooks and the apps you build. Use an API key to call mailfloss from your own tools. Use **Your apps** when you want other mailfloss users to connect to an app you build.

You can try the API from the [mailfloss Postman collection](https://www.postman.com/mailfloss-api-9976719/mailfloss-api/collection/5j71s41/mailfloss-api) or [Apidog docs site](https://swcgtl60qi.apidog.io/) before writing an integration.

## Before you start

Sign in to your mailfloss account as an owner or admin to create API keys or apps. If an API-key action returns **Access denied**, ask your account owner or admin for help.

Keep API keys and app secrets private. Never put them in a public collection, screenshot, support message or source repository. The examples below describe requests; they do not promise a particular verification result.

## Choose the right tab

| Tab           | Use it to                                                                                         |
| ------------- | ------------------------------------------------------------------------------------------------- |
| **API keys**  | View your keys. Owners and admins can create and manage keys for calls to the mailfloss API.      |
| **Webhooks**  | Choose events mailfloss sends to a URL on your server.                                            |
| **Your apps** | Owners and admins can create an app that other mailfloss users authorize to access their account. |

The **API docs** link opens the [developer reference](https://developers.mailfloss.com/).

## Create an API key

1. Open **Developers → API keys** and choose **Create API key**.
2. Give the key a name that describes its use, such as “Postman test,” and choose an expiry or **Never**.
3. Choose **Restricted** and select the permissions needed for your request. A single-email verification request needs **Verify emails** (`verify`).
4. Create the key and save it securely when it appears. The full key is shown only once.

Use the key as a Bearer token. Keep it server-side in your integration. If you lose it, create a replacement and update the tools that use it. Revoking a key immediately stops anything using that key.

## Try a request in Postman or Apidog

1. Open the [Postman collection](https://www.postman.com/mailfloss-api-9976719/mailfloss-api/collection/5j71s41/mailfloss-api) or [Apidog docs site](https://swcgtl60qi.apidog.io/).
2. Set up your request in a private working copy or private local session. Supply your mailfloss API key as the Bearer token; do not save it into shared or published examples.
3. Choose `GET /v1/verify` at `https://api.mailfloss.com`, and set the `email` query parameter to an address you are authorized to check.
4. Send the request. On success, inspect the JSON fields `status`, `reason` and `passed`. The verdict depends on the address; a successful HTTP request does not itself mean the address passed verification.

Each successful verification consumes one account credit. Start with one address. The [Quick Start](https://developers.mailfloss.com/quickstart) explains the response and links to the full API reference for further requests.

## Receive events with Webhooks

Open **Developers → Webhooks**. Webhooks are available on the Business plan or as an add-on. If the tab shows an availability message, check your account's access before trying to add one.

Choose **Add webhook** to configure the receiving URL, source and events. mailfloss sends a JSON POST to the URL when a selected event occurs. Open an existing webhook to manage it. Refer to the [developer documentation](https://developers.mailfloss.com/) for event payloads and delivery details before connecting your server.

## Test a webhook and check its deliveries

Open **Developers → Webhooks**, then open a webhook to see its own page.

- **Send test event** posts a sample payload to your endpoint, so you can check your setup without waiting for real activity. It makes one attempt.
- **Recent deliveries** shows the latest attempts for that webhook and how your server answered.

For real events, any 2xx response counts as delivered. If your server doesn't answer with a 2xx, mailfloss tries again up to 5 times over about 20 minutes, then turns **Sending** off for that webhook.

## Build an app for other mailfloss users

Owners and admins can open **Developers → Your apps → Create app**. An app uses an authorization flow so users can approve its requested permissions, rather than handing you their API key.

Follow [Build an app on mailfloss](https://developers.mailfloss.com/build-an-app) for the app name, redirect URIs, permissions and server-side setup. Save the client secret securely when it is shown. New, unverified apps have a warning on the consent page and a limit of 100 connections. Use the app's **Get verified** tab when you are ready to submit it for review.

An app you have connected to your account is managed separately under **Account Settings → Connected apps**, where you can disconnect it.

## Troubleshooting

- **The key is no longer visible:** the full key appears only at creation. Use your saved copy or create a replacement.
- **A restricted key gets a 403:** check that it includes the permission required by that request. Do not broaden access beyond what your integration needs.
- **The request fails:** read the API error's `code` and consult the developer reference. Keep the key out of any error report you share.
- **The Postman profile cannot be found:** use the collection link in this article, not `postman.com/mailfloss`.
- **You want to manage an app you connected:** go to **Account Settings → Connected apps**. **Your apps** is for apps you create.