curl -X POST 'https://api.resend.com/inboxes/inbox-id/labels' \
  -H "Authorization: Bearer $RESEND_API_KEY" \
  -H 'User-Agent: my-app/1.0' \
  -H 'Content-Type: application/json' \
  -d '{
  "name": "Urgent",
  "color": "#E93D82"
}'

# POST /inboxes/{inbox_id}/labels (Resend API)
Base URL: https://api.resend.com
Auth: Authorization: Bearer <RESEND_API_KEY>
Last verified: 2026-10-20

> Create a label on an inbox

## Critical Gotchas
* All requests must include a `User-Agent` header (e.g. `User-Agent: my-app/1.0`) or the API returns HTTP 403.

## cURL
curl -X POST 'https://api.resend.com/inboxes/inbox-id/labels' \
  -H "Authorization: Bearer $RESEND_API_KEY" \
  -H 'User-Agent: my-app/1.0' \
  -H 'Content-Type: application/json' \
  -d '{"name":"Urgent","color":"#E93D82"}'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| inbox_id | path | string | Yes | The Inbox ID or the inbox email address, such as `support... |
| name | body | string | Yes | The name of the label. Max 64 characters. Leading and tra... |
| color | body | string | No | The color of the label, as a `#RRGGBB` hex color. It is s... |

## Response (200 OK)
{"object":"inbox_label","id":"7f9c1d2e-4a6b-4c3d-8e15-9b0a7c6d5e34"}

---
Need an API key? Get one at https://resend.com/signup

POST

POST /inboxes/{inbox_id}/labels — Resend API

Resend API

Create a label on an inbox

Base URL: https://api.resend.com
Auth: Authorization: Bearer <RESEND_API_KEY>
Last verified: 2026-10-20 · upstream hash matched

Actions Try in browser→

Agents: curl -H "Accept: text/markdown" this URL
→ 218 tokens · Vary: Accept

Critical gotchas

All requests must include a User-Agent header (e.g. User-Agent: my-app/1.0) or the API returns HTTP 403.

cURL

curl -X POST 'https://api.resend.com/inboxes/inbox-id/labels' \  -H "Authorization: Bearer $RESEND_API_KEY" \  -H 'User-Agent: my-app/1.0' \  -H 'Content-Type: application/json' \  -d '{  "name": "Urgent",  "color": "#E93D82"}'

Parameters

Name	In	Type	Required	Description
inbox_id	path	string	Yes	The Inbox ID or the inbox email address, such as `[email protected]`. A value that contains `@` must be a valid email address, and any other value must be a UUID, or the request returns a 422. The address match is case-insensitive and never falls back to the inbox `name`. An address that matches no inbox returns a 404.
name	body	string	Yes	The name of the label. Max 64 characters. Leading and trailing whitespace is trimmed. Must not match another label on the inbox, compared without case.
color	body	string	No	The color of the label, as a `#RRGGBB` hex color. It is stored in uppercase. When omitted, a random color from the dashboard palette is used.

Response 200 OK

{
  "object": "inbox_label",
  "id": "7f9c1d2e-4a6b-4c3d-8e15-9b0a7c6d5e34"
}

Get a free Resend API key → sponsored

Affiliate link - we may earn a commission, at no extra cost to you.