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Probabilistic Forecasting for Teams

Stop guessing delivery dates. Use your team's historical performance data to forecast likely completion dates with confidence levels—not averages or guesswork.

What is Monte Carlo Forecasting?

Monte Carlo simulation is a technique that uses randomness to model uncertainty. Instead of producing a single estimate — which is almost always wrong — it runs thousands of simulated futures based on your team's real historical performance, then shows you the full range of likely outcomes.

The name comes from the Monte Carlo Casino in Monaco. Just like a casino uses probability to understand outcomes across thousands of bets, we use probability to understand outcomes across thousands of simulated cycles.

Feed it your history

Enter your team's past throughput or velocity — how many items or story points you completed per sprint or cycle.

10,000 simulations run

The tool randomly samples from your historical data over and over, simulating thousands of possible futures — fast, slow, and everything in between.

Get a range, not a guess

Results show you what's likely at 50%, 60%, 85%, and 95% confidence — so you can make decisions that match your actual risk tolerance.

The Tools

Two tools, two different questions. Both powered by the same Monte Carlo engine.

Date Forecaster

Given your remaining backlog and historical throughput, when will your team finish? Get probabilistic completion dates at multiple confidence levels.

Works with work item throughput or story points
P50, P60, P85, P95 completion dates
Buffer % estimates for stakeholder commitments
Risk factor slider for unknowns
Confidence timeline chart
Open Date Forecaster

Throughput Forecaster

Given a fixed time window, how much can your team realistically complete? Useful for sprint planning, PI planning, and capacity conversations.

Works with work item throughput or story points
P60, P85, P95 item counts
Multi-cycle projection (e.g. across 6 weeks)
Risk factor slider for interruptions
Distribution histogram
Open Throughput Forecaster
Which Tool Should I Use?

Use the Date Forecaster when…

  • You have a defined backlog and need to know when it'll be done
  • A stakeholder is asking "when will this ship?"
  • You're planning a release and need a date range to commit to
  • You want to show confidence levels to leadership

Use the Throughput Forecaster when…

  • You have a fixed time window and want to know how much fits
  • You're doing sprint or PI planning and need realistic capacity
  • You want to set expectations on scope before a quarter starts
  • You're evaluating what's achievable across multiple cycles
Frequently Asked Questions

How much historical data do I need?

A minimum of 6–8 completed iterations is recommended for meaningful results, though 12–20 provides a much more reliable forecast because it captures more of your team's natural variability.

If your team has changed significantly (new members, major process changes, or a different way of working), consider using only recent history that reflects how the team operates today.

What's the difference between 85% and 95% confidence?

85% confidence means that in 85 out of 100 simulated futures, your team finished by that date. It's a good target for internal planning commitments.

95% confidence is more conservative — use it for hard external deadlines, contractual dates, or anywhere the cost of being late is high.

What is the Risk Factor?

The risk factor models uncertainty by randomly reducing throughput or velocity during each simulated iteration.

For example, a 20% Risk Factor allows each simulated cycle to lose up to 20% of its sampled throughput. This helps account for uncertainty that isn't reflected in your historical data, such as holidays, onboarding, unexpected production issues, dependencies, or competing priorities.

It's best used sparingly to represent known sources of risk—not as a substitute for good historical data.

Why not just use average velocity?

Averages hide variability. If your team completes 8, 20, 10, and 18 items across four sprints, the average is 14 — but that number never actually happened. Monte Carlo uses the full distribution of your historical data, including the slow sprints, to give you a realistic picture of what's likely rather than what's mathematically average.

How often should I run and communicate a forecast?

Run a new forecast whenever new historical data becomes available—typically at the end of each sprint or iteration.

When sharing results, communicate a range of likely completion dates instead of a single target. For example: "We're approximately 85% confident we'll finish by May 12 based on the information we have today."

This helps stakeholders understand uncertainty and encourages conversations about acceptable levels of risk rather than treating a single date as a guarantee.

Keep in mind that forecasts naturally change over time. As work is completed, scope changes, or new historical data is added, projected completion dates will shift. Treat every forecast as a snapshot of what is most likely based on what is known today.

Why does my forecast change even when no work was completed?

Monte Carlo forecasting is probabilistic, meaning each simulation randomly samples from your historical data. Small differences between runs are normal.

Larger changes usually occur because the amount of remaining work changed, new historical data was added, or simulation settings (such as Risk Factor) were adjusted.

Is my data stored anywhere?

No.

All computation runs entirely in your browser. Nothing is sent to any server. Your inputs are saved only to your browser's localStorage so they persist between sessions on the same device.