We’re often asked what the differences are between QuantConnect and Quantopian and so we decided to address this question here transparently.

At QuantConnect we have a vision for the future of quant trading. We believe quantitative trading will be the primary investment vehicle of the future. We plan to be the open source, community driven vehicle which makes this future a reality.

Our community is building the most powerful, flexible and encompassing algorithmic platform in the world. Our system is fast, extensible and can support any asset class or market. It can work on a single desktop or as part of a massive cloud cluster. For us, this is incredibly exciting and we imagine a financial future powered by Lean. Hedge-funds, mutual funds, brokerages and individual traders can use our open source Lean platform to power their automated research and trading. Do you want to be part of the future?

The folks at Quantopian have built an interesting hedge-fund, and it looks like a pretty good service. We’re looking to show the facts here without opinion and let you choose for yourself.

Data Support
As a user, what assets can you backtest and trade, in what markets? What data resolutions are natively supported?
US Equities and Forex
Tick, Second, Minute, Hourly, Daily
US Equities, Fundamentals.
Minute, Daily Only
Backtest Processing Speed
How long did it take to run a 10 year backtest; 1 minute, 5 symbol algorithm?
63 Seconds 17 Minutes 8 Seconds
Development Environment
How easily can I create a real strategy?
Full Project IDE
Parallel Backtesting
Typesafe Compiler
We empower you to backtest locally, so you can work in Visual Studio. Our local backtesting Getting Started guide takes about 23 seconds!
Scripts Only
Single Backtest Only
Brokerage Support
Interactive Brokers and Tradier Brokerage
Trade Live On Web+Desktop
Interactive: $1 min, 0.5% max.
Tradier: $1 per trade flat rate. Currently for QuantConnect users only.
Interactive and ETrade
Trade Live Web Only
Interactive: $1 min, 0.5% max.
E-Trade: $8 per trade.

Objectively our data, technology and development environment out perform Quantopian. But what about the business? How do we stack up? These intangibles impact your experience as a user.

Staff / Company Team Size
How many people has it taken to build this community and technology? What is the output/person ratio?
3 People
You communicate directly with founders.
Approx. 31 People
Community Size
What are the officially reported community sizes?
12,000 Quants
Bootstrapped, organic, word of mouth growth
30,000 Quants
How much funding was required to achieve this? How much money have we taken from external investors? How capital efficient is the company?
Built On Only $200k Angel Funding
We’re funded by individual quant angels, who love what we do.
$24M Venture Funding
Business Focus
Infrastructure As A Service, White-Labeling
We host your strategies; you are our client. We chose a business model where our interests are aligned with you, and you can be sure we’ll be here in 10 years. Our primary motivation is aspirational; we are building the world’s best algorithmic trading platform to be the infrastructure of the future.
Recently Quantopian seems to be building a crowd-sourced hedgefund.

We’re proud to be maturing as a company; the open source community is growing, backtests and active coding is higher than its ever been. Its incredibly rewarding to see how people love QuantConnect! Join us to truly revolutionize and democratize quant finance.

The future of investment will be quantitative and we believe QuantConnect is the only company with the vision and technical ability to execute.

Founder @ QuantConnect


  1. You have a solid case here for QuantConnect, but you should mention technical and architectural differences too. QuantConnect uses .NET as a programming language, while Quantopian employs Python. The latter is more popular in data engineering circles and, arguably, in quant circles.

    QuantConnect is architecturally more complex and powerful in terms of SPI: you have Consolidators, Indicators, etc. modelled as such. Quantopian is more simplistic; however due to the fact that they use Python, you have all of the data processing features of Pandas available to you. I feel that QuantConnect is more sophisticated in terms of feature set, however this is a trade-off as it may force you to overengineer your strategy depending on the complexity. QuantConnect does much more “magic behind the scenes”, but this comes with a steeper learning curve.

    Quantopian’s web-based IDE is more powerful, although I know you are working to improve QuantConnect’s. However, in my opinion, the only way to currently develop with QuantConnect is to download Lean and use Visual Studio, which forces you to have a Windows machine or Virtual Machine. Not everybody will be happy with this. Moreover, it does not come with any data sources out-of-the-box to fetch daily data: I had to implement a custom interface to Yahoo to achieve this. So basically the initial experience is quite abrupt. But I know you’re working hard to improve all of this and I really appreciate your direct approach ๐Ÿ˜‰

    Another strong point for Quantopian at their present time is their documentation. QuantConnect calls “API Documentation” to a User Guide, which is extremely misleading. And this User Guide does not mention many features the platform does have (e.g. Consolidators). I searched for the actual API docs and couldn’t find them. So please consider publishing them as Lean’s source is very nicely documented, so you can generate high-quality docs automatically. (Unless they’re already online and I haven’t found them).

    Hope you appreciate my 2 cents ๐Ÿ˜‰

  2. Here’s one more plus point for QuantConnect. You offer extended hours data รขโ‚ฌโ€œ which may be crucial to some momentum-based algorithms. Quantopian doesn’t, but I wouldn’t be surprised if they launched this soon.

    1. Jared Broad says:

      Thank you for your reply Raul, definitely appreciate comment. We intentionally left out “X vs Y” language as it tends to be mostly religious. We’re language agnostic; open source .NET supports dozens right out of the box and we plan on making a bridge to others who aren’t compile time safe ๐Ÿ™‚

      Many people in the community use Linux and Mac to run Lean, indeed the whole QuantConnect cloud is powered on Ubuntu! You don’t need Visual Studio. I definitely need to update the documentation though! Its the very next thing on my todo list! ๐Ÿ™‚

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