Bulk Email Service — High-Volume SMTP Relay & Email API Gateway
Send high volumes of transactional and promotional email with a drop-in SMTP relay or a REST email API. Built for deliverability — dedicated and shared IPs, guided warmup, SPF/DKIM/DMARC, real-time analytics and 24×7 support — across India and 190+ countries.
What is a bulk email gateway?
A bulk email gateway is an outbound email infrastructure that lets applications and marketing teams send large volumes of email reliably — without running their own mail servers. It manages IP reputation, authentication, throttling and bounce handling so messages reach the inbox instead of the spam folder, whether you send 10,000 or several million emails.
SMTP relay is a drop-in path: you point your existing application, CRM or mailer at our SMTP servers and it starts sending immediately over an authenticated, encrypted connection. It works with virtually any language, framework or off-the-shelf tool that can send email, requiring almost no code changes.
A bulk email API is a programmatic path: your application calls a REST endpoint (with official SDKs) to send single or batched messages, attach metadata, and receive rich event data through webhooks. It gives you tighter control over templating, personalization and real-time delivery events at high throughput.
Two ways to send — SMTP relay & bulk email API
Use whichever fits your stack — or mix both. The same deliverability infrastructure powers each.
SMTP relay (drop-in)
Point any app, CRM or mailer at our secure SMTP servers on ports 587 or 465 with STARTTLS/SSL. Authenticate with credentials or an API key and start sending in minutes — no rewrite required. Ideal for WordPress, WooCommerce, ERPs and legacy systems that already speak SMTP.
Bulk email API (REST)
Call a clean REST API with official SDKs for popular languages to send single messages or batched jobs at scale. Pass templates, dynamic variables and metadata, then track opens, clicks, bounces and complaints in real time via webhooks — the modern path for product and campaign sending.
SMTP Relay vs Bulk Email API
Both deliver over the same reputation-managed infrastructure — the difference is how you integrate and how much event data you get back.
| Dimension | SMTP Relay | Bulk Email API |
|---|---|---|
| Integration effort | Minimal — change SMTP host and credentials | Light coding — call REST endpoint / SDK |
| Best for | Existing apps, CMSs, mailers, legacy systems | New builds, product email, high-volume campaigns |
| Sending speed at scale | High — connection and pipelining dependent | Very high — batch endpoints and parallelism |
| Setup (ports / protocol) | Ports 587 or 465, SMTP over TLS | HTTPS REST over port 443 |
| Event data / webhooks | Basic — delivery via logs and reports | Rich — opens, clicks, bounces, complaints |
| Language support | Any language or tool that speaks SMTP | Official SDKs plus any HTTP client |
| Personalization / templating | Handled in your app before sending | Server-side templates with dynamic variables |
Prefer sending product and OTP mail programmatically? See our email API and transactional email.
Built for deliverability & inbox placement
Sending is easy — landing in the inbox is the hard part. Our platform manages the reputation, authentication and encryption signals that mailbox providers use to decide whether your email is trusted.
Dedicated & shared IPs
Choose dedicated IPs for full reputation control or shared pools for lower volumes — each with guided warmup.
SPF, DKIM, DMARC & BIMI
Full domain authentication setup so mailbox providers verify and trust your sending domain and brand.
Sender reputation & feedback loops
Reputation monitoring and ISP feedback loops surface complaints early so you can protect deliverability.
TLS encryption
Opportunistic and enforced TLS on every connection keeps message content encrypted in transit.
Throughput, sending limits & scaling
Send speed scales with your plan and IP setup. Higher-tier plans and dedicated IPs unlock greater sustained throughput, while shared pools suit steady, lower-volume sending.
Send speed by plan
Throughput ramps with your plan tier and the number and type of IPs assigned. Dedicated IPs sustain higher volumes as their reputation matures, and capacity can be raised as your sending grows — no hard ceiling on scale.
Adaptive throttling & warmup
The platform automatically paces delivery to each mailbox provider's limits and warms new IPs gradually, increasing volume in controlled steps so you build reputation instead of tripping spam filters.
Gmail & Yahoo bulk sender compliance
Since February 2024, Gmail and Yahoo enforce stricter requirements for bulk senders. Our platform is built to help you meet every one of them so your mail keeps reaching the inbox.
SPF + DKIM + DMARC
All three must be configured and aligned for your sending domain. We set them up and validate alignment.
One-click unsubscribe
List-Unsubscribe headers with one-click opt-out are added and honored automatically on bulk mail.
Low spam-complaint rate
Keep complaints under 0.3% — ideally below 0.1%. Feedback loops and suppression help you stay well clear.
List hygiene & delivery controls
Protecting your reputation starts with your list. Automated hygiene tools keep bad addresses and unsubscribes out of your sending stream.
Bounce handling & auto-retry
Hard bounces are suppressed automatically; soft bounces are retried on an intelligent schedule before giving up.
Suppression & unsubscribe
Unsubscribes, complaints and past bounces are held in suppression lists so you never re-mail an opted-out address.
Real-time validation
Addresses are validated at send time to catch malformed, disposable and undeliverable recipients before they hurt reputation.
Analytics, logs & webhooks
Measure every send with real-time dashboards, searchable message logs and event webhooks — so you can act on deliverability the moment something changes.
Real-time analytics
Track delivered, opened, clicked, bounced and complained across campaigns and streams, exportable for reporting.
Searchable message logs
Per-message logs with status, timestamps and provider responses make troubleshooting individual sends fast.
Event webhooks
Push delivery, open, click, bounce and complaint events straight into your app or CRM in real time.
Bulk email use cases
OTP & transactional
One-time passwords, receipts, password resets and account alerts delivered fast on a dedicated stream.
Promotional campaigns & newsletters
Offers, product updates and newsletters to opt-in lists with tracking and one-click unsubscribe.
E-commerce
Order confirmations, shipping updates, cart reminders and post-purchase flows at high volume.
BFSI
Statements, transaction alerts and compliance notices with encryption and reliable delivery.
SaaS
Onboarding sequences, usage alerts, invoices and product notifications driven by your app.
Education
Admissions, results, fee reminders and course updates to students and parents at scale.
A bulk email partner built for deliverability
Trusted by 5,000+ businesses across India and 190+ countries, with 15+ years in messaging — reliable infrastructure, honest deliverability guidance and the reporting to prove your results.
Deliverability expertise
Authentication, warmup and reputation monitoring managed so more of your mail hits the inbox.
India + global reach
High-volume sending across India and 190+ countries from resilient, 99.9% uptime infrastructure.
Multichannel messaging
Pair email with SMS and WhatsApp for a single, coordinated communication stack.
24×7 human support
Real engineers help with setup, warmup and deliverability whenever you need them.
Pricing & plans
Volume-based plans for SMTP relay and the bulk email API, with dedicated and shared IP options. Scale up as your sending grows — talk to us for high-volume rates.
