The "Magic Number" you need to find to hit target!

How Many Deals Do You Actually Need? The Maths Behind Pipeline Forecasting

Most sales leaders and founders track the wrong number. They look at their pipeline total, the raw sum of deal values, glance at their annual target, and make a gut-feel judgement about whether they're on track. This is like checking if you have enough fuel for a road trip by looking at how full the tank is, without knowing how fast you're driving or how far you're going.

This post explains the precise mathematical framework for calculating the single most actionable number in sales: how many deals you need to add to your pipeline right now. Not by year end. Not next quarter. Right now, given your velocity, your win rate, and what you already have in play.

Why "How Many Deals?" Is the Wrong Starting Question

Before we get to the formula, we need to reframe the question.

Most people start with: "Do I have enough pipeline?"

The right question is: "Given how long my deals take to close, and how many of them I actually win, what revenue will the deals I add today produce, and by when?"

These are completely different questions. The second one forces you to anchor your pipeline to time and probability. Once you do that, the number of deals you need becomes a precise, calculable figure, not a guess.

The Four Inputs You Need

To calculate the number, you need four things:

1. Revenue target, for a specific future window, not the full year
2. Win rate, the percentage of closed deals you actually win
3. Average Order Value (AOV), the average value of a deal you close
4. Sales velocity, specifically your average sales cycle length in days

Input 1: Revenue Target (for the Right Window)

Your annual target is not the input. Using it creates two problems:

• It conflates months you've already passed with months ahead of you
• It ignores seasonality, as a £400k annual target isn't £33k/month if your business has peaks and troughs

The correct approach is to take your remaining monthly targets, ideally from a goals system that already accounts for seasonality, and use only the portion that's reachable given your sales cycle. More on that in the velocity section.

For now, establish: "What is my target for the specific future window I'm about to calculate?"

Input 2: Win Rate

Win rate is the percentage of closed deals that were won, as opposed to lost or disqualified.

Win Rate = Deals Won ÷ (Deals Won + Deals Lost)

Two important notes:

Use a meaningful time window. Don't include deals from three years ago if your business has changed significantly. A rolling 12-month window is usually right, long enough to be statistically meaningful, and recent enough to reflect your current market position and offering.

Exclude deals that are still open. A deal that's still in your pipeline hasn't been decided yet. Including it in the denominator would understate your win rate. Only count deals with a definitive outcome.

If you won 73 deals and lost 24 in the last 12 months, your win rate is:

73 ÷ (73 + 24) = 73 ÷ 97 = 75.3%

This 75.3% is not just a vanity metric. It becomes a multiplier that converts pipeline value into expected revenue, which is where the real maths starts.

Input 3: Average Order Value (AOV)

AOV is the mean deal value of your won deals over your chosen time window.

AOV = Total Revenue from Won Deals ÷ Number of Won Deals

Again, use the same rolling 12-month window as your win rate for consistency. If you use a longer historical average, you risk anchoring your model to deal sizes that no longer reflect your market.

A subtlety worth noting: AOV is the value of deals as they close, not as they enter the pipeline. New deals are often created with estimates that get revised up or down. Always calculate AOV from your closed/won historical data, not from current open deal amounts.

Input 4: Sales Velocity, the One Most People Get Wrong

This is the most important and most frequently misunderstood metric. Let's go deep.

What Sales Velocity Actually Is

Sales velocity has a common multi-variable definition used in revenue operations:

Sales Velocity = (Number of Deals × AOV × Win Rate) ÷ Average Sales Cycle Length

This formula produces a revenue per day figure, showing how much revenue your pipeline generates per day it exists. It's useful for comparing the health of different pipelines or teams.

But for the purpose of this calculation, knowing how many deals to add now, we need to isolate and focus on a single component of that formula: average sales cycle length.

Average Sales Cycle Length

This is the average number of days between when a deal is created and when it closes, either won or lost. You should calculate it from your historical won deals, since lost deals don't generate revenue and often close faster due to disqualification.

Average Sales Cycle = Sum of (Close Date − Create Date) for all Won Deals ÷ Number of Won Deals

If you're pulling this from a CRM, you're calculating the difference in days between deal.create_date and deal.close_date across your won deals in your trailing 12-month window, then averaging.

This number, let's say it's 74 days, is the single most important input in your model. Here's why.

The Critical Insight: Deals Entered Today Close at a Fixed Point in the Future

If your average sales cycle is 74 days, then a deal you add to your pipeline today will, on average, close 74 days from now.

This transforms the planning question entirely. You're not asking "do I have enough pipeline for the rest of the year?" You're asking: "do I have enough pipeline to hit my target 74 days from now?"

Any deal you add after today closes even further out. Any deal you added before today is either already closing or you've missed the window. This creates what we call the velocity window, the specific future period that your current prospecting activity will impact.

The Velocity Window: Targeting the Right Horizon

If today is the 25th of June and your sales cycle is 74 days, your velocity window closes around the 7th of September. Deals you add to your pipeline today will close in that window. Deals you add next week will close a week later.

This means:

• Your relevant revenue target isn't your annual quota, it's your combined monthly targets for July, August, and the first 7 days of September
• Any pipeline activity you do after today won't hit that window

To calculate your window target, take your monthly targets and apportion September proportionally:

Window Target = July Target + August Target + (September Target × 7/30)

This is your number. This is what your current prospecting activity needs to produce. Everything else, October, November, December, will be solved by pipeline activity you haven't started yet.

Separating Certain Revenue from Uncertain Revenue

Before you calculate the gap, you need to subtract revenue that's already committed, deals that are effectively certain to close within your window regardless of what you do today.

This might be:

• Already-won deals scheduled to close in the window
• Recurring contracts renewing in the window
• Any deal at a stage you consider effectively closed

Call this your locked revenue. It's committed and shouldn't count as pipeline you need to fill.

Adjusted Gap = Window Target − Locked Revenue

This is a critical step. If you have £27,000 in locked revenue against a £68,000 window target, your real gap isn't £68,000, it's £41,000. Many pipeline models skip this step and dramatically overstate how much new business development is required.

Accounting for Your Existing Open Pipeline

Here's where most pipeline forecasting models fail. They look at the number of open deals and either:

a) Assume all of them will close (too optimistic), or
b) Ignore them entirely and calculate from zero (too conservative)

The correct approach is to calculate the expected value of each open deal, using your win rate as the probability:

Expected Value of Deal = Deal Amount × Win Rate

A £25,000 deal at a 75% win rate has an expected value of £18,750. That's the statistically correct contribution of that deal to your revenue forecast. It doesn't mean you'll get 75% of the money, you'll either get 100% or 0%, but across many deals, the expected value is accurate.

If a deal is effectively won already, verbally agreed, in legal, etc., you can override its probability to 100%:

Expected Value of Won Deal = Deal Amount × 100%

Sum the expected values of all your open pipeline deals:

Open Pipeline Expected Value = Σ (Deal Amount × Probability) for all open deals

Now your adjusted gap becomes:

Revenue Gap = Window Target − Locked Revenue − Open Pipeline Expected Value

If this number is zero or negative, you have sufficient pipeline. If it's positive, you have a gap to fill.

The Number: Deals Needed

Now we can calculate the headline figure.

Each new deal you add to your pipeline has an expected revenue contribution of:

Expected Revenue per New Deal = AOV × Win Rate

If your AOV is £4,566 and your win rate is 75.3%, each new deal you add is worth £3,438 in expected revenue.

To fill your revenue gap:

Deals Needed = Revenue Gap ÷ (AOV × Win Rate)

Round up, because you can't have 0.4 of a deal:

Deals Needed = ⌈ Revenue Gap ÷ Expected Revenue per Deal ⌉

So if your revenue gap is £25,000 and your expected revenue per deal is £3,438:

Deals Needed = ⌈ 25,000 ÷ 3,438 ⌉ = ⌈ 7.27 ⌉ = 8

That's the number. Not a rough estimate. Not a feeling. Eight deals, created and qualified in your CRM now, will statistically produce the revenue required to hit your velocity window target.

Why This Number Is So Important

The number of deals you need is important not because it tells you what to do, it tells you the minimum viable pipeline for hitting your next revenue milestone.

Without it, you're making one of two errors. You're either:

• Over-pipelining, spending time on too many deals, spreading your attention across opportunities that don't all need to be in play at once, and burning capacity on deals that close outside your target window
• Under-pipelining, assuming your existing pipeline is enough, then discovering in week nine of a twelve-week cycle that you've missed the window to fix it

The velocity window calculation solves the second problem specifically. By the time you realise you're short, it's too late to add deals that will close in your target period. The only way to avoid this is to calculate the number now, at the start of the window, when you still have time to act.

What Do You Do With the Number?

Knowing you need eight deals is only useful if you know how to generate eight deals. And this is where most business development conversations stop too early.

A deal doesn't materialise from nothing. Before a deal exists in your CRM, there was a prospect. Before a prospect, there was a conversation. Before a conversation, there was an outreach. Before an outreach, there was a name in a list.

Each of those transitions has a conversion rate:

• What percentage of people you reach out to agree to a conversation?
• What percentage of conversations result in a qualified opportunity?
• What percentage of qualified opportunities become a deal in your pipeline?

If you know these rates, you can work the number backwards:

Conversations Needed = Deals Needed ÷ Conversation-to-Deal Conversion Rate

Outreaches Needed = Conversations Needed ÷ Outreach-to-Conversation Conversion Rate

This is the full funnel picture, and it's a substantial topic in its own right. But the foundational point is this: the deals needed number is the bridge between your revenue target and your daily activity. Without it, business development is a volume game you're playing blind. With it, you have a mathematically grounded answer to the question every founder and sales leader faces every week, am I doing enough?

Summary: The Full Formula

1. Sales Cycle (days) = Avg days from deal creation to close (won deals, last 12m)

2. Velocity Window End = Today + Sales Cycle Length

3. Window Target = Sum of monthly targets within the velocity window

4. Locked Revenue = Committed/certain deals closing in window

5. Open Expected Value = Σ (open deal amount × win rate)

6. Revenue Gap = Window Target − Locked Revenue − Open Expected Value

7. Expected per Deal = AOV × Win Rate

8. Deals Needed = ⌈ Revenue Gap ÷ Expected per Deal ⌉

Eight lines of arithmetic. The last number is your answer. Track it weekly, update it as deals close or are added, and you'll always know, precisely, whether your pipeline is healthy or not.

The calculations described in this post can be applied to any CRM data. The key inputs, win rate, AOV, and sales cycle length, are available in every CRM's closed deal history. If you're not calculating them regularly, you're flying blind.

The framework above works as a starting point for any business, but the reality is that every business has its own set of nuances that a simple model won't capture. Your deal mix might skew heavily toward a handful of high-value clients that distort your AOV. Your win rate might vary significantly by deal source, sector, or deal size. Your sales cycle might be 30 days for one type of work and 120 days for another. When those variables exist, applying a single blended number to all of them produces a figure that looks precise but isn't accurate, and an inaccurate number is often worse than no number at all.

That's where the complexity compounds: locked revenue, recurring contracts, seasonal targets, pipeline stage probabilities, and the relationship between deal type and close rate all interact in ways that aren't obvious until you pull the data apart. Getting those variables right, and building a model that accounts for all of them, is the difference between a dashboard that confirms your gut feel and one that genuinely tells you something you didn't know.

The Growth Architect builds this for you. If you want to understand the unique variables at play in your pipeline, and have a custom model built that takes all of them into account, get in touch.