OCPI Network Simulator
The OCPI Network Simulator visualizes OCPI message flows in real time. Build a virtual charging network of CPOs, eMSPs, hubs, and chargers, trigger charging sessions, and watch every OCPI request and response travel between parties, from authorization through session start to CDR settlement.
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When a driver plugs into a charge point that belongs to somebody else, a conversation happens that the driver never sees. The charge point operator has to authorize a token it did not issue, open a session, meter it, close it, and send a charge detail record to the provider who will actually bill for it. Tariffs have to agree. Identifiers have to line up. Every one of those steps is a message defined by OCPI, and every one of them is somewhere an integration can quietly go wrong.
This simulator runs that conversation in the browser. Build a small network of charge points, operators, providers and a hub, start a session, and watch the exchange unfold message by message. You can open any message and read its payload, which is usually the fastest way to understand a part of the protocol that a specification describes in the abstract.
It is free and needs no login, because there is nothing to protect: no real endpoint is contacted and no data leaves the page.
Where to go next
To understand the protocol behind what you are watching, start with an introduction to the Open Charge Point Interface and then the message flows between a CPO and an eMSP. When you are ready to check a real integration rather than a simulated one, the OCPI testing tool runs conformance suites against your own endpoint, and the guided scenarios break things on purpose so you learn to recognise the failures.
Common questions
What does the simulator actually simulate?
A roaming network: charge points, a charge point operator, an e-mobility service provider, and the hub between them. You drive a charging session through it and watch the OCPI messages the parties exchange, in the order they exchange them, with the payload of each one.
How is this different from the testing tool?
The simulator is for understanding: it shows you what a correct exchange looks like, end to end, with nothing at stake. The OCPI testing tool is for proving: it runs conformance suites against a real endpoint and reports where that endpoint departs from the specification. Most people use the simulator first and the testing tool once they have something to test.
Do I need an endpoint or an account?
Neither. The simulator runs in the browser with no login. Nothing you do here touches a real network.
Which OCPI versions does it cover?
OCPI 2.1.1, 2.2.1 and 2.3.0. The message set changes between versions, which is usually the first thing that surprises a team upgrading, so the simulator lets you switch version and watch the flow change.