What is ProjectX? The API Gateway Behind TopstepX
ProjectX is the platform and API TopstepX is built on, developed and owned by ProjectX Trading LLC. The clean mental model (Topstep, TopstepX, ProjectX and your tools), which prop firms still use it, and where its API is and isn't open.
What ProjectX is, how it relates to TopstepX, and why it's the thing you actually connect to when you automate a Topstep account.
Short answer: ProjectX is the trading platform and API that TopstepX is built on. Topstep's own site says TopstepX "is developed and owned by ProjectX Trading LLC." When you click buy in TopstepX, or when your code places an order, it goes through ProjectX. Other prop firms used to license ProjectX too. Today it's effectively a Topstep platform.
The one-sentence version
TopstepX is the platform you see. ProjectX is the company and the infrastructure underneath it.
ProjectX describes itself in its API docs as "a complete end-to-end solution for prop firms and evaluation providers": account setup, risk rules, liquidations, statistics, permissions. The prop firm sets the rules and pays you. ProjectX runs the machinery that enforces them.
Why the distinction matters
Most traders never need to think about ProjectX. You open TopstepX, you click buy, it works.
It matters the moment you want to automate. Then the question is how a program places an order without a human clicking, and the answer is the ProjectX Gateway API. Your API key authenticates you to it, and any automation (a Sierra Chart bridge, a Python script, a copier) talks to it. Topstep's own description: TopstepX API access "is powered by ProjectX and billed separately from your Topstep subscription."
How the pieces fit together
| Layer | What it is | You touch it when |
|---|---|---|
| Topstep | The prop firm: the Combine, the funded accounts, the rules, the payouts | You buy an evaluation and follow the risk rules |
| TopstepX | Topstep's trading platform | You trade by hand |
| ProjectX | The platform, gateway and API underneath TopstepX | You automate: your code connects here |
| Your tools | Sierra Chart, Python, a copier | You generate the orders that get sent to ProjectX |
Which prop firms use ProjectX?
In practice, one: Topstep.
ProjectX used to be licensed to a long list of futures prop firms. In November 2025 it told those firms it was ending third-party licensing, with support winding down by February 28, 2026, and moved exclusively to Topstep. The Gateway API docs now list only two platforms in their navigation: TopstepX and The Futures Desk, which Topstep acquired.
If a firm advertises "ProjectX" today, check their own platform page before you buy.
What ProjectX does not change
A documented API makes automation a supported path, not a hack. But the API is only open where Topstep opens it:
- Combine and Express Funded: API trading allowed.
- Live Funded: "The API Gateway is built for the simulated environment and isn't available on Live."
- Anywhere: orders must come from your personal device. No VPS, no VPN, no remote server.
The full rules, stage by stage, are in does Topstep allow automated trading.
Next
- How to get your TopstepX (ProjectX) API key →
- Sierra Chart to TopstepX: the free trade copier →: a working ProjectX integration you can read the code of.
- Does Topstep allow automated trading? →
Sources retrieved 2026-11-05. Prop platforms change; check the linked pages before you act on them.
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