OTP from Vietnam.
Delivered worldwide.
Flat $0.022 per delivered OTP. Crypto prepaid, no KYC — no rejections for crypto, Web3 or high-risk verticals.
Median API ack
< 1s
Carriers
Viettel · Vinaphone · Mobifone · Vietnamobile
OTP reach rate
90%
Every undelivered code is a lost user.
Cheaper than Twilio. Friendlier than carriers. Paid in crypto.
Crypto prepaid, no chargebacks
Top up in USDT, USDC or BNB. Balance credited within one block confirmation. No card, no bank, no chargeback risk.
Zero-KYC. Cryptographic keys only.
API keys are SHA-256 hashed before storage. We log delivery status, never the OTP itself. Operator dashboard purges 30-day rolling.
Four Vietnamese carriers, one endpoint.
Voice and SMS routes across every major Vietnamese network. Mobifone is SMS-only and priced separately.
Pay only for delivered codes.
Every send returns a webhook with delivered or failed status. Failed sends never debit your wallet — unlike Twilio, you don't pay for unreachable numbers.
{
"status": "delivered",
"id": "otp_8f2…",
"charged": 0.022
}90% delivery, no single point of failure.
Multiple upstream providers fail over automatically. If one route drops, the next picks up — your user still gets the code.
Ship in seven lines
Idiomatic TypeScript, Python and Go SDKs. OpenAPI 3.1 spec generated from production routes.
await nexo.otp.send({
phone: "+84901234567",
code: "482917"
})Flat pricing. Big bonuses.
One price for every carrier. The more you top up, the more we throw in. Pay only for delivered codes.
Pay-as-you-deliver
- Same flat rate for Viettel, Vinaphone, Vietnamobile
- Mobifone (SMS) priced at $0.027
- Failed sends never charge your wallet
- No subscription, no idle fee
The more you top up, the more we throw in.
- $100 – $499+10% credit
- $500 – $1 999+15% credit
- $2 000 ++25% credit
First deposit ≥ $100 → +5% extra (one-time, stacks with tier bonus)
Bonus credit is spend-only — not withdrawable.