Features
Engineered for developer productivity.
FlashAuth delivers complete transactional phone authentication through clean, robust HTTP APIs designed for modern stacks.
Mock Sandbox Mode
Test verification flows in local development and CI/CD without incurring SMS charges. Test keys (pk_test_*) generate a random code you copy from the dashboard inbox.
Turnkey User Sessions & JWTs
Exchange verified codes for signed HS256 JWT access tokens (15m TTL) and sliding refresh tokens (30d) directly with /v1/auth/login.
Cooldowns & Abuse Defense
Automated protection against SMS pumping fraud. Enforces 30s resend throttles, 5m code expiration, and per-IP rate limiting.
Native REST Endpoints
Drop-in HTTP APIs requiring zero proprietary client SDKs. Works seamlessly with cURL, fetch, Python requests, Go net/http, and PHP.
API Key Management
Separate test and live production keys with instant revocation. Set custom monthly volume quotas and country allowlists.
In-House Auth Replacement
Replace weeks of plumbing Redis queues, carrier error retries, and token databases with two clean HTTP calls.
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