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Real-time open & click tracking - No setup required
Test Multi-Channel Verifications
Need to inspect and debug outbound application emails? Try SmtpCove, our free SMTP Sandbox.
Simulate SMS messaging locally. Perfect for integration testing, user OTP registrations, and automated notification testing.
Follow these simple steps to integrate and test simulated SMS notifications in your application.
Click the Get Free API Key button above to instantly generate a 24-hour key and Account SID.
Pick one of our predefined virtual numbers or enter a custom destination target number below.
Point your SMS client or API caller to the endpoint URL and add authorization details.
Trigger the message from your app. The incoming mock SMS appears here in real-time!
Our mock gateway is built to be a drop-in simulator. It is compatible with any standard client tool, including cURL, Postman, custom HTTP clients, and libraries like axios or requests.
Accepts both JSON payloads and form-encoded data. Parameters map flexibly: from/sender, to/recipient, and body/text/message.
Select one of our popular mock sandbox numbers below to view its incoming inbox messages instantly.
Waiting for mock SMS traffic. Send a POST request to this number from your app, or use the Simulator Form on the right.
curl -X POST https://yourdomain.com/api/sms/send \
-u "YOUR_ACCOUNT_SID:YOUR_AUTH_TOKEN" \
-H "Content-Type: application/json" \
-d '{
"from": "+1234567890",
"to": "",
"body": "Your test message body here"
}'⚙️ Mock Gateway Compatibility:
application/json and application/x-www-form-urlencoded request payloads.Bearer Token, Basic Auth (username:password), or body/query params (apiKey, token, or key).from / sender, to / recipient, and body / text / message.Connect your backend services directly to our simulated gateway. Generate your private integration key instantly — valid for 24 hours. Need longer? Contact us to extend.
✓ Instant self-service — no email required
✓ 24-hour key validity (contact us to extend)
✓ 1-hour message TTL by default
✓ Compatible with Basic Auth & Bearer Token
Click Get Free API Key above to instantly generate your personal sk_sms_... token and Account SID. Valid for 24 hours.
Direct your custom SMS integration client to target our sending endpoint: /api/sms/send.
Open this dashboard for your target number. Trigger your backend SMS flows; messages will instantly stream on the screen.
Modern web application development frequently relies on automated alerts, multi-factor authentication (MFA), and one-time password (OTP) verification codes delivered via SMS. However, sending test messages to physical carrier networks during developer stages introduces significant expenses, security concerns, and regulatory bottlenecks. Our mock sandbox acts as a virtual telecom simulator designed specifically to bypass these issues. For multi-channel email automation testing, you can also leverage our premium Temp Mail utility.
A mock SMS gateway is a development sandbox that intercepts outgoing message requests from your application's SDK. Instead of transmitting these payloads to real telecommunication channels, the simulator parses the API call, saves it temporarily in our database, and streams the message to your dashboard in real-time, working similarly to a temporary email address inbox.
Use this gateway for local debug environments, CI/CD testing pipelines, QA verification cycles, and offline app demonstrations. It eliminates Twilio, Plivo, or Vonage billing charges while protecting your developers from carrier rate limits and regulatory filtering (like A2P 10DLC compliance). Use it in tandem with our Email HTML Tester to check multi-channel verification alerts.
Configuring the simulator is simple. Point your application's custom SMS provider endpoint to our gateway's POST route and authenticate using your free developer token. Any standard JSON or URL-encoded payload formatting with matching parameter names will be successfully accepted. Read our quick Integration Steps above to get started.
This simulator is strictly intended for application integration testing and tutorial demonstration purposes. It does not possess any hardware hookups to real cell towers and cannot be utilized to send text messages to real people.
To keep the sandbox clean and secure, all mock SMS logs are automatically and permanently deleted 1 hour after they are received. Do not use real customer phone numbers or sensitive private details in your test messages.
We secure your credentials by storing them in a one-way hashed format, meaning your raw API keys can never be read or retrieved from the database. For added safety, keys are only shown as masked previews (e.g., sk_sms_...abcd) on your admin screens.
Our platform relies on automated bot-protection monitors and rate-limiting modules to ensure stability. Abuse, high-volume stress testing without coordination, or attempting to flood public sandbox endpoints will result in automatic IP blocking.
Users of the SMS Mock Sandbox are fully responsible for ensuring their mock content conforms to legal standards. Attempting to inject malware scripts, command payloads, or highly offensive text to public views is strictly prohibited.
Moving past the sandbox? Connect your app to a live telecom provider. Listed below from budget-friendly to premium enterprise solutions.
Highly cost-effective SMS and voice APIs. Excellent choice for startups and high-volume developers on a budget.
The global gold-standard developer SMS API. Offers extensive tooling, documentation, and dynamic messaging features.
Reliable international delivery rates and customizable verification flows. Highly compatible with existing setups.
Enterprise-grade omnichannel messaging platform. Highly optimized routing networks with premium delivery assurances.
Common questions about using our SMS API Gateway Sandbox.