Sandbox mode
Test the full API surface using sandbox keys and free test credits. Deterministic test numbers return predictable outcomes, and webhooks fire identically to live production.
Sandbox is a full mirror of the live API. It has its own keys (sk_test_*), its own wallet (free credits that don't expire), and returns deterministic responses that let you test the full range of success and error paths.
Deterministic test data
- +919999999999 — always delivers successfully after 300ms.
- +919999999911 — always fails with INVALID_NUMBER.
- +919999999922 — always fails with DND_BLOCKED.
- +919999999933 — always fails with TEMPLATE_MISMATCH.
- +919999999944 — times out, useful for testing your retry logic.
- OTP 999999 — always verifies successfully on /v2/otp/verify.
Webhooks fire identically in sandbox, so you can point a local ngrok URL and walk through the full flow before touching production.
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