generated: '2026-09-01'
method: searched
source: https://tempmailgrab.com/api-docs
also:
- https://tempmailgrab.com/email-testing-api
- https://github.com/sathishbanoth-coder/tempmailgrab-js
summary: >-
  There is no separate test-mode account, no test/live key pair, and no sandbox host — every call runs
  against production with a single tmg_live_ key class. What the provider ships instead is a first-class
  fixture injector, which for an email-testing API is the equivalent surface: createTestMessage pushes a
  synthetic message through the real ingestion, MIME-parsing, OTP-extraction and realtime pipeline so a
  consumer can develop message-handling logic without waiting on outside mail.
modes:
  test_live_separation: false
  key_prefixes:
  - prefix: tmg_live_
    mode: live
    note: The only documented key prefix; no tmg_test_ counterpart exists.
  sandbox_host: null
fixtures:
- name: Synthetic message injection
  operation_id: createTestMessage
  path: POST /api/v1/inbox/{id}/test-message
  description: >-
    "Inject a synthetic email into your inbox — useful for developing and testing your message-parsing logic
    without waiting for a real email." It exercises the same parsing and realtime path as inbound mail.
  effects: real (the message is stored in the inbox and fires webhooks)
- name: Webhook payload signing
  export: signWebhookPayload(secret, body)
  package: tempmailgrab (npm)
  description: >-
    Generates a valid X-TMG-Signature for a body of your choosing, so a consumer can produce legitimate
    deliveries against their own receiver in tests without waiting for real mail.
- name: Interactive playground
  url: https://tempmailgrab.com/api-docs
  description: >-
    "Try it — Interactive Playground. Paste your API key and run live requests against the real API."
    Endpoint pickers for createInbox, listInboxMessages, createTestMessage and listWebhooks. It calls
    production with your own key; it is a console, not an isolated sandbox.
  requires_key: true
test_isolation:
  mechanism: inbox-per-test
  description: >-
    The documented testing pattern is one disposable inbox per test rather than a shared QA mailbox, so
    parallel runners never contend for the same message. The npm package ships a Playwright fixture
    (tempmailgrab/playwright) that hands each test its own address, and prefixes are sanitised to
    [a-z0-9] with a random suffix appended so parallel runs cannot collide.
  teardown: >-
    None required — every inbox carries a TTL and is purged with its messages. deleteInbox exists for
    explicit teardown in place of waiting out the TTL.
test_values:
  published: false
  note: >-
    No magic addresses, test cards, or reserved identifiers are published — inbox addresses are randomly
    generated at creation. Nothing invented here.
free_tier:
  note: >-
    A free developer account with an API key can be created from https://tempmailgrab.com/dashboard with no
    credit card; the provider states it is "fully functional on the free tier with a single concurrent inbox
    and the standard 24-hour TTL."