Use Maileroo to send one-time codes by SMS, WhatsApp, voice, Telegram or email, then verify them with a single API call. You set the sender profiles, limits and retry rules. We handle delivery and track every attempt in real time.
Send one-time codes by SMS, voice call, WhatsApp, Telegram, or email from one API, then check the code your user enters. Pay a flat fee for each successful verification plus the channel's delivery cost, from a prepaid balance with no monthly commitment.
Multi-Channel VerificationOne API to send OTPs by SMS, voice, WhatsApp, Telegram or email. Pick the channel that suits each user. Perfect for sign-ins, account access, and other verification flows.
Send secure one-time codes directly to users' phones for fast, familiar verification across sign-ins and account actions.
Deliver verification codes through automated voice calls when SMS is unavailable or another channel works better.
Send one-time codes through WhatsApp and give users a familiar verification experience on a channel they already use.
Reach users with secure verification codes through Telegram while keeping the same verification flow inside Maileroo.
Send secure one-time codes by email for sign-ins, account access, and other verification flows while keeping everything inside the same Maileroo setup.
Product TourA quick walkthrough of sending, tracking and verifying a code.
How It WorksYou request a code, we deliver it on the channel you choose, and you check what the user typed. That's the whole integration.
Verification ToolsRoute codes across multiple providers, set your rules once, and see what happened to every verification. Built on redundant infrastructure with 99.99% uptime.
Choose which channels a flow can use, how long codes stay valid and how often they can be requested. Add a fallback order like SMS, then WhatsApp, then voice, so users still get their code when one channel doesn't get through.
Every request shows its channel, status, attempts and timestamp. Know at a glance whether a code was sent, verified, expired, cancelled or failed, without opening a log file.
Send and check codes with a simple REST API, then subscribe to events like verification.verified to update your app the moment a user passes. No polling and no custom state tracking.
Send a test code from the dashboard using any sender profile and channel, then enter it yourself. Catch a misconfigured channel or a wrong expiry setting before it reaches production.
Customer StoriesFrom startups and agencies to established businesses, teams around the world rely on Maileroo to simplify email infrastructure, improve deliverability, and scale with confidence.
I really like it. It is a new service, so there is always the possibility that as it grows, it might deteriorate over time, but my experience so far has been exceptional. The instructions for adding domains are clear and easy to follow, domain verification after adding the correct DNS records is very fast, the emails are sent promptly, and so far none of them have ended up in spam folders.
What a Joy to work with, I couldn't be more impressed with the services provided by Maileroo.com. From the moment I signed up, the experience was seamless and efficient. The platform is incredibly user-friendly, making it easy for me to manage my emails and campaigns effortlessly.
We were searching for a new SMTP provider, after the one we were using raised the prices for the 3rd time - in 2 years. We Found Maileroo and couldn't be happier. Everything works smoothly, prices are top-notch, and their support is friendly and helpful.
I'm not a techie person or programmer, and this is my first time using an SMTP server. I was having some issues setting up one of my tools with maileroo's SMTP servers. A quick support chat inquiry led me to one of the co-founders who spent about an hour with me to solve my issue. In the end, it was all my own human error. We were able to fix the issue, but the best thing about the whole experience was how patient and pleasant Areeb was. Just a really great experience, especially for someone like me who isn't a developer or IT specialist.
I've been through a number of mail services over the last few years and maileroo is a standout for me. Everything about it. The underlying service is great, the architecture is solid and its super reliable and delivery is fast. As well as that the UX for the interface is also really well crafted making it a pleasure to use. Beyond that the service levels are superb, fast and useful. Lastly, the price point is superb. It really is hard to fault Maileroo, I'd give it 6 stars out of 5 if I could
FAQEverything developers ask about channels, code rules, delivery, billing, abuse protection and webhooks before they send their first verification.
SMS, voice call, WhatsApp, Telegram and email, all through one API. Each sender profile chooses which channels it allows.
Codes are 4 to 8 digits, 6 by default. A code is valid for 10 minutes by default. You can set this per verification anywhere from 3 minutes to 24 hours.
5 by default. After that the verification fails and can't be approved, so a code can't be brute-forced.
Webhooks fire for every step: created, sent, verified, failed, expired and cancelled. A failed event with no sent event before it means the code couldn't be sent. An expired event with no sent event before it means sending kept failing until the code expired.
Yes. Temporary errors are retried automatically, and if a route fails we switch to another delivery route.
You pay a small fee per message for the channel, plus a verification fee ($0.03) only when a code is verified successfully. Failed or abandoned verifications never incur the verification fee.
Yes. GET /v1/verify/balance returns your balance and a rate card. It lists the verification fee and the per-country price range for every channel.
You top up a prepaid Verify balance. We reserve a small hold when a code is sent and settle it at the actual cost once it's known. Holds for codes that never went out are released. Auto-recharge is available in the dashboard.
Each sender profile can have a rate limit, either per destination or for the whole profile, with a window you choose. Repeated requests beyond the limit are rejected.
FeaturesEverything behind reliable delivery at any volume: sending, verification, routing, and the analytics to see what happened, from first API call to millions a month.
Send transactional and bulk emails through reliable SMTP infrastructure built for speed, security, and deliverability.
Integrate email delivery into your applications using powerful APIs built for flexibility, scalability, and performance.
Separate transactional and marketing traffic into isolated sending streams to protect reputation and keep critical emails fast.
Receive and route incoming emails directly into your applications using flexible automation and processing workflows.
Create and deliver marketing campaigns designed to increase engagement, reach, and customer retention.
Receive real-time event notifications for deliveries, opens, and clicks for storage and automation workflows.
Monitor email performance with detailed insights, reporting tools, and actionable delivery metrics in real time.
Capture, inspect, and validate every message in a safe sandbox, with authentication checks and spam analysis before going into production.
Build integrations faster using SDKs, code examples, and resources for modern application development.
