Market Zeitgeist
Every market has a zeitgeist. Cycles tell you which one you are in.
A zeitgeist is the mood of a time. In markets, in the economy and in the world around them, that mood has a length, a phase and a direction, and it can be measured. Market Zeitgeist measures it: research for readers, ready-made scanners for observers, and an API for teams that build their own analysis.
Cycles Frontier Technology Part of Cycles IQ
Know which cycles to trust.
The scanner tells you which cycles are in a market right now. The Cycles Knowledge Graph answers the three questions that follow, which today are answered by experience and by eye:
- Can I trust this cycle? Its age, its length drift, and the probability that it survives one more swing.
- Is it part of something bigger? How many related markets share the band and turn in the same weeks.
- Has this kind of call worked before? Every projected turn scored against what came, including the misses.
A way to be wrong in public, and to get better because of it.
One method, several fields
Cycles do not stop at the stock exchange.
The same detection and forecasting routines are applied wherever rhythmic behaviour shows up in data. Financial markets are the core; the other fields inform the readings.
Equities, indices, FX, commodities, crypto
Dominant cycles, phase and projections per symbol and timeframe.
Growth, inflation, rates, liquidity
Longer cycles in macro series and how they align with market cycles.
Conflict, sentiment, generational patterns
Recurring patterns in the environment markets operate in.
Solar activity, geomagnetism, climate
Physical rhythms with a documented relationship to human behaviour.
Who it is for
From a first look to a full integration.
See the current cycle position without building anything
Ready-made scanner pages for markets and assets, updated on a schedule, plus the research newsletter for the reasoning behind the readings.
Run your own scans, keep your own process
The analyzer web app for any symbol and timeframe, and API access when the results should land in your own tools.
Cycle methods inside your systems
Tested backend routines behind a REST API and an MCP server; the Cycles AI skill lets AI coding tools build screens and pipelines on top of it in hours, not weeks.
Research & tools
Five ways in.
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Research Open
Read on Substack
The newsletter
Cycle readings of the markets that matter and the reasoning behind them.
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Scanners & analyzer Pro
Open the analyzer
The Pro application
Prepared scanner pages for markets and assets, and the analyzer for your own symbols and timeframes.
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API Usage-based
Plans and limits
The Cycles API and MCP server
Cycle detection, cyclic RSI, phase and projections by the call, from your code or from your AI client.
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Membership By invitation
Why Cycles IQ
Cycles IQ
The full stack with a person behind it: API, MCP server, AI skills, the advanced analyzer, pre-built dashboards, the Cycles Knowledge Graph, and onboarding with Lars.
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Local stack Cycles IQ only
Ask about it
Your own cycles stack, on your own infrastructure
The cycle engine, the API and the MCP server inside your own network, next to your own data. For Cycles IQ members.
AI
Cycle analysis that language models can run, and read.
The engine is reachable from AI tools, and the rules for using and interpreting it ship as skills. The model does not guess what a cycle chart means; it follows the same interpretation rules an analyst would. The AI tooling is part of the Cycles IQ program. Why the skills matter, in one page.
The Cycles engine inside your AI client
Claude, Cursor and other MCP clients call cycle detection, CRSI and forecasts directly. Sign-in through your Market Zeitgeist account, no keys pasted into prompts.
How to run an analysis, and which endpoint does what
A packaged skill that explains the method to the model: the order of steps, which endpoint serves which purpose, and what a valid result looks like. AI coding tools build screens and pipelines on the API from it.
Hand a cycle chart to the model, get a clean reading
Prepared skills read the cycle charts you created and return a structured, plain-language interpretation. The interpretation rules are predefined in the skill, which keeps hallucination and misreading out of the result.
Method
Measured, not assumed.
Every reading starts from the data: detect the dominant cycles in a series, score their stability, locate the current phase, and only then project. The same routines run in the newsletter, in the scanners, in the analyzer and behind every API call. Cycle lengths are not fixed in advance; they are found in the data and re-measured as it changes.
- Decoding the Hidden Market Rhythm, Part 1: Dynamic Cycles — the method for finding and trading dominant cycles, with indicator source code (2nd edition, 2017)
- Decoding the Hidden Market Rhythm, Part 2: Metonic Cycles — a non-linear approach to cycles that influence financial markets (2014)
- Finalist at the Technical Analyst Awards 2022 in two categories, Best Specialist Product/Research and Most Innovative New Product, for the cycle analysis technology behind the FSC cycles app
- Lars von Thienen serves on the board of the Foundation for the Study of Cycles
Every market moves in cycles, and the cycles morph: a length that dominated a series for two years fades, another takes over, and the right side of the chart no longer matches the one you calibrated on. For twenty-five years I have built the detrending, spectral and validation routines that measure this in the here and now instead of assuming it. What changed is the application layer: with the method encoded as skills, you describe the screen and the AI builds it. The measurement took decades. Using it takes an afternoon. Lars von Thienen, founder of Market Zeitgeist and developer of the WhenToTrade cycle engine, author of Decoding the Hidden Market Rhythm, board member of the Foundation for the Study of Cycles
Start with the research. Talk to us about the rest.
The newsletter is open to everyone. API access and Cycles IQ begin with a short conversation about what you want to do.