REST API · SDKs · Webhooks · 99.9% Uptime

Seamless Custom API Integration

Bridge the gap between your applications and our global communication gateway. Use our RESTful APIs to automate SMS, WhatsApp, and Voice within your own software — with SDKs for every major language and a free sandbox to test instantly.

99.9%

API Uptime SLA

<100ms

Avg Latency

50K+

Requests/sec

Official SDKs

cheapbulksms_api.py

SMS

Voice

            // Send Bulk SMS via API

            POST /v1/sms/send

            {

            "api_key": "YOUR_API_KEY",
            "to": "+919876543210",
            "message": "Your OTP is 482910",
            "sender_id": "CBSMS",
            "type": "transactional"
            }

            // Response: 200 OK

            { "status": "queued", "msg_id": "cb_9x2k1" }
          

            // Send WhatsApp Template Message

            POST /v1/whatsapp/send

            {

            "api_key": "YOUR_API_KEY",
            "to": "+919876543210",
            "template": "order_confirmation",
            "params": ["Rahul", "ORD-1042"],
            "media_url": "https://cdn.store/receipt.pdf"
            }

            // Response: 200 OK

            { "status": "sent", "wam_id": "wam_8f2p9q" }
          

            // Initiate Outbound Voice Call

            POST /v1/voice/call

            {

            "api_key": "YOUR_API_KEY",
            "to": "+919876543210",
            "from": "DID_NUMBER",
            "action": "play_audio",
            "audio_url": "https://cdn.you.com/otp.mp3"
            }

            // Response: 200 OK

            { "call_id": "vc_7h3n4r", "status": "initiated" }
          

Free Sandbox Test API in minutes

API Requests 2.1M today

Developer First

Developer First Infrastructure

Everything built with developers in mind — clean REST endpoints, full webhook support, comprehensive docs, and SDKs that get you live in one afternoon.

🌐

RESTful Voice API

Trigger automated voice calls, IVR flows, conference bridges, and call recordings using simple HTTP requests from any language or framework.

⚡

Real-Time Webhooks

Receive instant server-side notifications for call status changes, DTMF inputs, SMS delivery receipts, and WhatsApp read events pushed to your endpoint.

📡

Voice QoS & Low Latency

API media routes through low-latency edge nodes across 5 global regions, ensuring every integrated call maintains enterprise HD audio quality standards.

🔗

CRM & ERP Ready

Native connectors for Salesforce, Zoho, HubSpot, SAP, and Oracle, plus a flexible webhook layer for any proprietary business software stack.

🔐

Secure Authentication

API Key, OAuth 2.0, and JWT authentication options. IP allowlisting, request signing, and TLS 1.3 enforced on every endpoint by default.

📈

Scalable Concurrency

Handle up to 50,000 API requests per second with our load-balanced, auto-scaling cloud infrastructure built for high-growth SaaS platforms.

📊

Real-Time Delivery Reports

Every SMS, WhatsApp message, and voice call returns live delivery, read, and engagement data via webhook or polling endpoint per message ID.

🧪

Free Sandbox Environment

Test your entire integration in a live sandbox with real API responses but no credits consumed. No credit card required to access the sandbox.

📚

Comprehensive Documentation

Interactive API docs with live "try it" console, code examples in Python, Node.js, PHP, Java, and cURL. Postman collection downloadable instantly.

🔄

Bulk Send via Single Request

Send to 100,000 recipients in a single API call using our bulk endpoint. Responses include per-recipient status with individual message IDs.

🌍

Global Number Pool API

Programmatically provision local DID numbers in 100+ countries, assign them to campaigns, and release them via the number management API.

🛡️

Compliance & DLT API

Built-in API support for DLT template registration checks, TRAI compliance validation, and opt-out list management — fully automated.

Official SDKs

Your Language, Our SDK

Official client libraries maintained by CheapBulkSMS for every major programming language. Install with one command and send your first message in minutes.

🐍

Python

pip install cheapbulksms

🟩

Node.js

npm install cheapbulksms

🐘

PHP

composer require cheapbulksms/sdk

☕

Java

Maven / Gradle

💎

Ruby

gem install cheapbulksms

🦀

go get cheapbulksms/go-sdk

API Reference

Core API Endpoints

Every channel covered. Every action available via a clean, versioned REST interface with consistent response schemas.

POST /v1/sms/send

Send SMS

Send single or bulk SMS to any mobile number globally. Supports transactional, promotional, OTP, and unicode message types.

POST /v1/whatsapp/send

Send WhatsApp Message

Send approved template messages, free-form replies, images, videos, PDFs, and interactive button messages via WhatsApp API.

POST /v1/voice/call

Initiate Voice Call

Place an outbound call, play audio, trigger IVR, or connect to an agent. Full DTMF input capture and recording support.

GET /v1/reports/delivery

Delivery Reports

Fetch real-time delivery status for any message ID. Bulk status polling available for campaign-level reporting.

POST /v1/contacts/import

Import Contacts

Bulk-import contacts from JSON or CSV. Supports custom field mapping, duplicate removal, and DND auto-filtering.

GET /v1/balance

Account Balance

Query your current credit balance, plan details, and usage metrics programmatically for billing automation.

POST /v1/webhooks/register

Subscribe your server URL to real-time events: SMS delivery, WhatsApp read receipts, call status, DTMF, and reply events.

GET /v1/numbers/available

Available DID Numbers

List available local and toll-free numbers by country and area code for dynamic provisioning in your application.

POST /v1/templates/validate

Validate DLT Template

Check a message body against your registered DLT templates and TRAI rules before sending to avoid rejections.

DELETE /v1/contacts/optout

Opt-Out Contact

Remove a contact from all outbound communication lists and sync the opt-out across SMS, WhatsApp, and Voice channels.

Integration Guide

Live in 4 Simple Steps

From sign-up to your first API-triggered message live in production — in under one afternoon.

Create Account & Get API Key

Sign up at CheapBulkSMS, verify your account, and generate your API key from the developer dashboard. Access the sandbox immediately — no approval wait.

Install the SDK

Run one install command for your language (pip, npm, composer, or Maven). Import the library and set your API key. Your first test request is 3 lines of code.

Test in Sandbox

Use the free sandbox environment to send test SMS, WhatsApp, and voice calls with full API responses. No live credits consumed during sandbox testing.

Go Live in Production

Switch your API base URL to production, top up your balance, and deploy. Your integration is now sending real messages with full delivery monitoring.

Use Cases

Built Into Every Platform

From SaaS startups to enterprise ERP systems — see how developers use CheapBulkSMS API to power communication at scale.

💻

SaaS Applications

Embed SMS OTP, WhatsApp notifications, and voice alerts directly into your SaaS product using our REST API and webhooks for real-time events.

🛒

E-Commerce Platforms

Trigger order confirmations, shipping updates, abandoned cart SMS, and WhatsApp delivery notifications automatically from your order management system.

🏢

Enterprise CRM & ERP

Integrate CheapBulkSMS into Salesforce, SAP, or custom ERP workflows to auto-send transactional alerts, field agent updates, and approval notifications.

🏦

Banking & FinTech

Send 2FA OTPs, transaction alerts, and fraud warnings with sub-3-second delivery via SMS or WhatsApp API, with full delivery confirmation per event.

📡

IoT & Monitoring Systems

Connect IoT devices and server monitoring systems to CheapBulkSMS API for instant SMS or voice alerts when thresholds are breached or anomalies detected.

🚀

Startups & Developers

Launch communication features in your app within hours using our free sandbox, interactive docs, and SDKs. Scale from 100 to 10 million messages without changing a line of code.

Security

Enterprise Security & Compliance

Every API call is protected by enterprise-grade security standards — so your data and your customers’ data stay fully protected.

🔑

API Key & OAuth 2.0

Multiple authentication methods including API key, OAuth 2.0, and JWT tokens. Choose the model that fits your security architecture.

🌐

TLS 1.3 Encryption

All API traffic is encrypted with TLS 1.3. No HTTP connections permitted. Every request and response is secured end-to-end.

🛡️

IP Allowlisting

Restrict API access to specific IP addresses or CIDR ranges. Unauthorised IP requests are rejected at the gateway before reaching your account.

📋

SOC 2 & GDPR Compliant

CheapBulkSMS is SOC 2 Type II certified and fully GDPR-ready. All data is stored in your chosen region with full data residency controls.

Integrations

Works with Your Existing Stack

Plug CheapBulkSMS API directly into the platforms and tools your team already uses.

Salesforce

HubSpot

Zoho CRM

SAP

Oracle CX

Freshdesk

Zendesk

Shopify

WooCommerce

Magento

Stripe

Razorpay

Zapier

Make (Integromat)

AWS Lambda

Google Cloud Functions

Firebase

Postman

REST API

Webhooks

FAQ

Frequently Asked Questions

Everything developers need to know about integrating CheapBulkSMS API.

Sign up for a free account at CheapBulkSMS, navigate to the Developer section in your dashboard, and generate your API key. You can immediately start testing in the free sandbox environment without adding credits. Full API documentation with interactive examples is available at docs.cheapbulksms.com.

Yes. Every account includes a free sandbox environment that mirrors the production API exactly. You can test SMS, WhatsApp, and voice call endpoints with real API responses without consuming any live credits. The sandbox uses a dedicated base URL and your production API key.

Official SDKs are available for Python, Node.js, PHP, Java, Ruby, and Go. Every SDK is maintained by CheapBulkSMS, fully documented, and installable via the standard package manager for each language. Alternatively, you can integrate directly with the REST API from any language using HTTP requests.

The default rate limit is 500 requests per second per API key. Enterprise plans can request higher limits up to 50,000 requests per second. If you exceed your rate limit, the API returns a 429 response with a Retry-After header. Bulk send endpoints accept up to 100,000 recipients in a single request.

Webhooks are delivered via HTTPS POST to your registered endpoint. Our system retries failed webhook deliveries up to 5 times with exponential backoff over 30 minutes. You can view all webhook delivery attempts, response codes, and payloads in your developer dashboard for debugging.

Yes. CheapBulkSMS API covers 200+ countries and 500+ carrier routes globally. You specify the recipient number in E.164 format (+country code + number) and our API automatically routes to the optimal carrier for that destination. International DID number provisioning is also available via the numbers API.

CheapBulkSMS provides a /v1/templates/validate endpoint that checks your message content against your registered DLT templates before sending. You pass your DLT template ID and the message body, and the API confirms compliance or returns specific violation details. DND filtering is applied automatically on every send request.

Yes. CheapBulkSMS has native Zapier and Make (Integromat) integrations that expose all API actions as no-code triggers and actions. You can connect CheapBulkSMS to 5,000+ apps without writing a single line of code. For custom workflows, our webhook support makes it easy to connect any platform that can receive HTTP callbacks.

Start Building Today

Your First API Call in Under 5 Minutes

Sign up free, grab your API key, and start sending SMS, WhatsApp, and Voice messages programmatically — no credit card required to access the sandbox.