> ## Documentation Index
> Fetch the complete documentation index at: https://docs.b2bsignals.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# API keys

> Make, replace or turn off your workspace API key, and see who can manage it and what it can do.

An API key lets your code act as this workspace. Manage it in **Settings** › **API & MCP**, under **API key**.

## Before you start

* **Your role.** Only owners and admins can make, replace or turn off a key. Other members can see its status.
* **Your plan.** "API keys come with a paid plan (Software or Custom)." On Free, the card shows **See plans** and you can't make a key. See [Plans](https://docs.b2bsignals.ai/getting-started/plans.md).
* **One key per workspace.** Making a new one replaces the old one.

## Make a key

**1. Open the API key card**

Go to **Settings** › **API & MCP**. It says "No key yet."

**2. Press Make a key**

Your full key appears. It starts with `b2b_sk_`.

**3. Press Copy and store it somewhere safe**

We show it once and don't keep a readable copy. Afterwards, the card shows only a masked version with the last 4 characters.

![API key row with a masked key and its menu](https://mintcdn.com/b2-b-signals-llc/u5yYe4FZtFc5vtD_/images/developers/api-key-and-ai-approval.png?fit=max\&auto=format\&n=u5yYe4FZtFc5vtD_\&q=85\&s=c487e16a2426d5c16053b0585848c187)

After you make a key, the card shows who made it and only the last 4 characters.

Making a key costs nothing and sends nothing.

## Use a key

Send it in the `X-API-Key` header:

```bash theme={null}
curl -H "X-API-Key: $B2B_API_KEY" \
  "$B2B_API_BASE/leads/?limit=10"
```

Your base URL is in [Developers overview](https://docs.b2bsignals.ai/developers/overview.md#base-url).

## What a key can do

There are no scopes. A key has owner-level access to its one workspace. It can't reach any other workspace.

Some actions always need a signed-in person, and some need **Let AI tools approve and send messages** turned on. See [Permissions](https://docs.b2bsignals.ai/developers/overview.md#permissions).

> [!WARNING]
>
> Treat your key like a password. Don't put it in a shared document, a public repository or code that runs in a browser. Anyone who has it can act as your workspace.

## Replace a key

Do this if a key may have leaked, or when someone who had it leaves.

**1. Open the menu on the API key card**

Press **⋯**, then **Make a new key…**.

**2. Confirm**

The current key stops working right away. Anything that uses it, like a Zapier step or your code, needs the new one.

**3. Copy the new key and update your tools**

This includes any [MCP link](https://docs.b2bsignals.ai/developers/mcp.md), because the link carries the key.

You can't undo this. The old key can't be brought back.

## Turn a key off

Press **⋯**, then **Turn off…**. Anything that uses it stops working right away. You can make a new key any time.

Turning a key off doesn't stop your webhooks. They have their own signing secrets. To stop one, see [Webhooks](https://docs.b2bsignals.ai/developers/webhooks.md#turn-a-webhook-off).

## Troubleshooting

> [accordion] I lost my key
>
> We can't show it again. Make a new key, then update everything that used the old one.

> [accordion] I get 401 Invalid API key
>
> The key is wrong or was replaced. Check that the whole key is in the `X-API-Key` header and that nobody made a new one.

> [accordion] I can't make a key
>
> If you're a member, ask an owner or admin. If you're an owner or admin, your workspace may be on Free, which has no API keys. See [Plans](https://docs.b2bsignals.ai/getting-started/plans.md).

> [accordion] I get 403 on one action, but other calls work
>
> A person must do that action while signed in. The `detail` field says so. See [Permissions](https://docs.b2bsignals.ai/developers/overview.md#permissions).

## Related

> [card] [Developers overview](https://docs.b2bsignals.ai/developers/overview.md)
>
> Base URL, permissions and limits.

> [card] [MCP](https://docs.b2bsignals.ai/developers/mcp.md)
>
> Use your key with an AI tool.


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