Revenue Forecast Calculator

A bookings forecast estimates the sales value a team expects to book in a period. This calculator adds the deals already closed won in the period to the open deals weighted by their probability of closing, and shows the best case in which every eligible open deal is won. Sales leaders, founders and finance partners use it to compare the expected result with the target and to decide where to focus before the period ends. It forecasts booked sales, not recognized revenue or cash.

For each eligible open deal, multiply its amount by its close probability (50 % counts as 0.5) and add up the results: that is the weighted open pipeline. Add the value already closed won in the period, and you obtain the forecast bookings. The result is a currency amount for the period.

The best case adds the full amount of every eligible open deal to the won value, as if all of them closed. It is an upper bound, not a likely outcome. The gap between the forecast and the best case shows how much of the result still depends on open deals.

If you set a forecast period, only open deals whose expected close date falls within it (both dates included) are eligible; deals outside the period or without a close date are excluded and the calculator tells you so. Without a period, every listed deal is included.

What each term means

Won sales in period

Booked deals already closed won within forecast period.

Where to find it: Booked value of deals already marked closed won with a close date inside the period, from your CRM. These deals must not appear again in the open deal list.

Open deal amount

Value of an opportunity not yet closed.

Where to find it: Amount of each open opportunity, as recorded in the CRM, in the same currency and on the same basis as the won value (for example booked contract value, excluding taxes). Remove deals that are already won or lost.

Close probability

Estimated likelihood the deal closes won; 0–100%.

Where to find it: Estimated chance that the deal closes won, between 0 and 100. Prefer probabilities derived from your own history by stage or deal type over individual guesses, and review them when a deal changes stage.

Expected close date

Forecast date the customer decision will occur.

Where to find it: Date on which the customer decision is expected, from the opportunity record. Optional, but required for a deal to be counted when a forecast period is set.

Forecast period

Period included in the forecast and quota comparison. Leave both dates empty to include every listed deal.

Where to find it: Optional start and end dates of the period you forecast, usually the current month or quarter. Fill in both dates or leave both empty to include every listed deal.

Forecast bookings

Expected booked sales, not recognized revenue or guaranteed cash.

Hypothetical example: a team has already won 20,000 this quarter and has two open deals: 40,000 at a 50 % probability and 20,000 at 25 %.

1. Forecast bookings20,000 + 40,000 × 50% + 20,000 × 25% = 45,000

Forecast bookings = 45,000

40,000 × 50 % = 20,000 and 20,000 × 25 % = 5,000, so the weighted open deals total 25,000; 20,000 + 25,000 = 45,000 of forecast bookings. The best case is 20,000 + 40,000 + 20,000 = 80,000. If the 40,000 deal slipped to next quarter, the forecast for this quarter would fall to 25,000 and the best case to 40,000: one deal carries a large share of the result.

Hypothetical numbers, used to show the calculation. Not real company data.

Use the forecast during the period, typically weekly or before a forecast call, to estimate where bookings are likely to land. Comparing the forecast with the target tells you whether the remaining open deals are realistically enough, and comparing the forecast with the best case shows how much depends on deals that are not yet decided.

It also helps decide where to spend time. Deals with a large amount and a mid-range probability have the largest effect on the forecast; moving one of them forward, or confirming that it will slip, changes the picture more than any small deal.

Finally, it is a check on CRM discipline. If the forecast changes sharply from one week to the next while few deals actually closed, probabilities or close dates are probably being edited without a change in the buyer’s situation.

A bookings forecast, a sales target and a cash flow plan answer different questions. The target is what the team committed to book. The forecast is what the team expects to book, given what is won and what is open. Cash flow is when money actually arrives, which depends on invoicing schedules, payment terms and collection. A deal booked on the last day of the quarter may be invoiced monthly over a year and paid 60 days after each invoice; it fully counts in bookings and barely appears in the quarter’s cash.

Recognized revenue follows accounting rules and is usually spread over the period in which the service is delivered. Presenting a bookings forecast as a revenue or cash forecast leads to wrong decisions on hiring or spending, so label the result clearly and let finance translate it into revenue and cash.

The quality of a forecast depends on its probabilities. Instead of letting each representative type a percentage, measure from closed deals in your CRM what share of value at each stage was eventually won, by segment, and use those rates as defaults. Review them every quarter and adjust a specific deal only for documented reasons, such as a signed proposal or a lost budget.

The forecast is an expected value, not a promise. With few open deals the actual result will rarely equal it: each deal is either won in full or not at all, so the outcome lands at one of several distinct values around the forecast.

The larger the share of the forecast that comes from weighted open deals rather than won deals, the more uncertain it is. Early in a period most of the forecast is weighted; near the end it should be mostly won.

A forecast close to the target with a best case far above it means the target depends on several open deals. A best case below the target means that even winning every eligible deal would not be enough within the period.

Practical levers

• Set default probabilities by stage from your own closed-deal history and review them every quarter.
• Keep expected close dates current, and require a reason when a date is moved.
• Remove won and lost deals from the open list as soon as their status changes.
• Review the largest weighted deals first in forecast meetings: they move the result the most.

Common mistakes

• Counting a won deal twice, once in won value and again in the open list.
• Presenting forecast bookings as recognized revenue or expected cash.
• Using optimistic probabilities that are never compared with actual outcomes.
• Including open deals whose close dates fall after the period.
• Reporting a single number without the best case or the share still uncertain.

Scenario comparison

The scenarios shift every probability by ±10 percentage points and every open deal amount by ±10 %. In the example, the probability shift gives 39,000 and 51,000, and the amount change gives 42,500 and 47,500; the won value does not move. These ranges are illustrative, not statistical confidence intervals.

If a small change in probabilities moves the forecast across the target, the outcome depends on judgement calls on a few deals. Say so explicitly when you report the number.

The calculator treats probabilities as independent and correct. In reality they are estimates, often optimistic, and deals can be linked (one budget, one decision maker).

It assumes amounts will not change. Discounts, reduced scope or currency effects at signature make actual bookings lower or higher than the recorded amount.

It forecasts bookings for the deals you enter. New deals created and won within the period are not included unless you add them, and it does not forecast recognized revenue or cash collection.