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Choose a tool to test charging protocols, exchange real-time messages or convert text to speech. New to OCPP? Follow the step-by-step guides below to get started.

MQTT WebSocket Client

Publish and subscribe to MQTT messages in your browser. Test QoS, retained messages, Last Will and scheduled publishing.

Open MQTT Client

Sparkplug B Simulator

Simulate industrial nodes and devices over MQTT WebSocket. Test metric reporting, remote commands and online/offline events.

Open Sparkplug B Simulator

OCPP Simulator

Test connections, registration and transaction flows against an OCPP 1.6 server in your browser without a physical charge point.

Open OCPP 1.6 Simulator

WebSocket Testing Tool

Connect to a WebSocket server, send test messages and inspect live responses and message logs.

Open WebSocket Tool

TTS Text to Speech

Enter text and select a voice to synthesize audio for read-aloud and voiceover testing.

Open Text to Speech (Chinese)

OCPP Command and Message Examples

Load an Example and Start Testing

Watch the OCPP Simulator Video Tutorial (Chinese) · OCPP 模拟器中文版

What Is OCPP?

OCPP (Open Charge Point Protocol) enables communication between charging stations and charging management systems. During development and integration testing, a simulator can replace a physical charger to verify registration, heartbeat, authorization and transaction messages.

Use the OCPP 1.6 Simulator and OCPP 2.0 Simulator to test charging protocols. For general bidirectional messaging, try the WebSocket Testing Tool.

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