Exclusively built by Cloopen for login, registration, password reset, and transaction verification — where latency matters most. Physically isolated channels with carrier-grade priority ensure sub-second response and 95%+ delivery rate even during peak marketing hours.
Every step from send to verify is engineered for extreme performance and security.
Fully isolated from marketing and notification SMS with independent gateway clusters and direct connections to global carriers. OTP traffic is never deprioritized or queued. Backed by Cloopen's decade of enterprise communications expertise.
Real-time quality scoring across 200+ carrier links plus adaptive failover algorithms switch to the optimal path in milliseconds. Cloopen connects directly to major carrier SMSCs worldwide, bypassing all intermediaries.
If it doesn't arrive, you don't pay. Charges apply only when the verification code is successfully delivered — the industry's first transparent billing model. Cloopen's confidence in product quality.
Built-in SMS Pumping defense, number risk database, IP/device rate limiting, and behavioral profiling to block all suspicious requests. Cloopen's security team blocks over 1M attacks per day on average.
When SMS fails or times out, automatically and seamlessly switches to Voice fallback — users always receive their codes. Cloopen's multi-channel convergence is industry-exclusive.
Certified to SOC2 Type II, GDPR, and ISO27001, covering 200+ countries and regions across Southeast Asia, Europe, and the Americas. Localized data residency and cross-border transfers fully compliant with regional regulations.
Traditional SMS platforms route all message types through the same channel. During major promotions, marketing SMS floods severely squeeze OTP traffic — your users can't receive verification codes, causing registration conversion rates to collapse.
Our OTP channel is deployed independently from access layer to carrier gateways, carrying zero non-verification traffic. This means:
From registration to sensitive operation confirmation, one API solves all OTP scenarios.
Phone verification + anti-bot signup
Two-factor authentication security layer
High-security identity recovery
Critical payment & transfer confirmation
Binding change / withdrawal / permission updates
New device trust relationship setup
Multi-factor identity final confirmation
Virtual asset trading / anti-theft
We're not here to compete on price — we're here to solve fundamental OTP problems.
| Key Metric | Twilio Verify | Vonage SMS API | MessageBird | Cloopen OTP ★ |
|---|---|---|---|---|
| Physically Isolated Channel | ✗ | ✗ | ✗ | Yes |
| Pay-on-Delivery Billing | ✗ | ✗ | ✗ | Yes |
| P50 Latency <3s | ≈ 2-4s | ≈ 3-5s | ≈ 3-8s | < 3s ★ |
| Domestic Delivery ≥98% | ≈ 85-92% | ≈ 87-93% | ≈ 90-95% | ≥ 95% ★ |
| AI Anti-Fraud Protection | Fraud Guard | Fraud Defender | Basic rate limit | Full protection ★ |
| Voice Fallback | Supported | Supported | Extra setup | Phase 2 ready |
| Global Compliance (GDPR/SOC2) | SOC2 | GDPR/SOC2 | GDPR | GDPR/SOC2/ISO27001 ★ |
| APAC Local Tech Support | English only | English only | EN only | EN / 9+ languages ★ |
| SLA Availability | 99.95% | 99.95% | 99.9% | 99.99% ★ |
From request intake to terminal delivery, each layer has independent protection mechanisms ensuring secure and reliable OTP service operation.
ML-based anomaly detection that identifies and intercepts large-scale verification code theft attacks targeting high-value number ranges. Real-time monitoring per number/IP/device request frequency and patterns.
Configure frequency limits across multiple dimensions including phone number, IP address, device fingerprint, App ID, etc. Supports sliding window and token bucket algorithms.
Integrates carrier blacklists, virtual number databases, recent complaint numbers, and multi-source data for real-time risk assessment. High-risk numbers trigger enhanced verification or blocking.
Uses cryptographically secure pseudo-random number generators to produce verification codes, eliminating predictability risks. Code validity, length, and character set are fully configurable. TOTP mode supported.
RESTful API design, clear documentation, official SDK coverage for mainstream languages.
One command installs the official SDK via npm/pip/maven/gradle.
Initialize with Account ID and auth credentials from console.
Call send() with target phone number and AppID, millisecond response.
Call verify() to complete validation with async callback or webhook support.
Officially maintained SDKs covering mainstream languages, continuously updated, fully open-source.
Start your free trial of Cloopen OTP today — no credit card required.
