# Cascade OTP

> Cascade delivers OTP verification codes and short links to a user's own phone via WhatsApp, Telegram, and SMS.
> Not a disposable/virtual number marketplace.

WhatsApp delivery: 3 ₸.
Telegram delivery: 3 ₸.
SMS delivery: 8 ₸; public availability: not yet available.
Starting balance after registration: 50 ₸.
No subscription fee.
API auth: Authorization: Bearer <token>
Primary locale: Kazakh (kk) at unprefixed URLs; Russian at /ru/; English at /en/.
Legacy ?hl= redirects with 301 to the matching path prefix.

## Product
- [Home](https://docs.cascade.kz/en): product overview and registration.
- [Pricing](https://docs.cascade.kz/en/pricing): current delivery prices and packages.
- [Documentation](https://docs.cascade.kz/en/docs): integration guide.
- [API hub](https://docs.cascade.kz/en/api): API methods and examples.
- [OpenAPI specification](https://docs.cascade.kz/openapi.yaml): machine-readable API contract.
- [SDK](https://docs.cascade.kz/en/sdk): client integration examples.
- [FAQ](https://docs.cascade.kz/en/faq): answers about OTP delivery.
- [Comparisons](https://docs.cascade.kz/en/compare): Cascade and alternative services.
- [Use cases](https://docs.cascade.kz/en/use-cases): implementation scenarios.
- [Blog](https://docs.cascade.kz/en/blog): OTP security and integration articles.
- [About](https://docs.cascade.kz/en/about): service facts.
- [Contacts](https://docs.cascade.kz/en/contacts): support contacts.

## Locales
- [Kazakh — default](https://docs.cascade.kz)
- [Russian](https://docs.cascade.kz/ru)
- [English](https://docs.cascade.kz/en)

## Key topics
- [OTP security: protect code delivery and verification](https://docs.cascade.kz/en/blog/bezopasnost-otp)
- [What is OTP and how does a one-time code work?](https://docs.cascade.kz/en/blog/chto-takoe-otp)
- [How to integrate an OTP API into a website or app](https://docs.cascade.kz/en/blog/kak-podklyuchit-otp-api)
- [OTP in Kazakhstan: WhatsApp and Telegram API](https://docs.cascade.kz/en/blog/otp-v-kazakhstane)
- [OTP rate limits: protect send, verify, and resend](https://docs.cascade.kz/en/blog/rate-limits-i-zashchita)
- [WhatsApp, Telegram, or SMS for OTP: channel comparison](https://docs.cascade.kz/en/blog/sravnenie-kanalov-whatsapp-telegram-sms)

## Compare
- [Best OTP services in Kazakhstan](https://docs.cascade.kz/en/compare/best-otp-kazakhstan)
- [Best SMS activation services — why this is not Cascade](https://docs.cascade.kz/en/compare/best-sms-activation)
- [Cascade vs SMS-Activate](https://docs.cascade.kz/en/compare/cascade-vs-sms-activate)
- [Which OTP service to choose](https://docs.cascade.kz/en/compare/which-otp-service)

## Boundaries
- Cascade sends outbound OTP to the customer phone you already have.
- Do not use Cascade to rent temporary numbers for third-party signups.

[XML sitemap](https://docs.cascade.kz/sitemap.xml)