Growth Marketing Glossary

Forecast

fore·castnoun

A reasoned prediction of what's coming — sales, demand, revenue — that planning and budgeting hang on. And the verb for making it.

data + assumptionsproject forwardforecast
Schematic — past data and assumptions projected into future values
Term
Forecast
Is
A prediction of future values
Of
Sales, demand, revenue, traffic
Read with
Pipeline, budget, demand planning

Parts of speech & senses

forecast · noun
  1. A prediction of future values — such as sales, demand, or revenue — based on historical data and assumptions. "The Q4 sales forecast guided inventory orders."
  2. A statement of expected future conditions, as in a weather forecast.
forecast · verb
  1. To predict or estimate a future value or condition based on data and assumptions. "They forecast demand from the pipeline and seasonality."

Forms, tenses & usage

Inflections & tenses: plural forecasts · verb forecast / forecasts / forecast (or forecasted) / forecasting
Common phrases & collocations: sales forecast, demand forecast, revenue forecast, forecast accuracy, weather forecast, rolling forecast
Register & usage: Standard. Past tense is usually 'forecast'; 'forecasted' is also accepted. Everyday use includes the weather forecast.
Related forms & abbreviations: forecasting (noun), forecaster (noun)

What a forecast is

A forecast is an informed estimate of the future — most often a number, like next quarter's sales, demand, revenue, or traffic, projected from historical data and explicit assumptions. It is the bridge between what has happened and the decisions that depend on what will happen: how much inventory to order, how much to budget, how many people to hire, what targets to set.

A forecast is a prediction, not a promise. Its quality depends on the data and assumptions behind it, and a good forecast states its assumptions and its uncertainty rather than presenting a single number as certain. The point is not to be exactly right but to be useful and honestly bounded.

How forecasts are used in marketing

In growth and marketing, forecasts drive resourcing and accountability. A sales forecast built from pipeline and conversion rates sets revenue expectations; a demand forecast shapes inventory and media flighting; a traffic or lead forecast sizes the funnel needed to hit a goal. Forecasts also become targets, which is where care matters: a forecast bent to match a desired number stops being a prediction and becomes wishful thinking that misleads the decisions it feeds.

The discipline is method and humility. Use the right approach for the horizon and data (from simple trend-and-seasonality models to pipeline-weighted or statistical methods), state assumptions, track forecast accuracy over time to improve it, and present ranges rather than false precision. A forecast you measure against actuals gets better; one you never check stays a guess.

Forecast as a verb and other senses

As a verb, to forecast is to make the prediction — 'forecast demand,' 'forecast the quarter.' Its past tense is usually 'forecast' (sometimes 'forecasted').

Outside business, forecast keeps the everyday sense of predicting future conditions, most familiarly the weather forecast. All senses share the idea of casting an estimate forward in time from current information.

Worked example. A team treats its sales forecast as a target to please leadership rather than an honest prediction, quietly inflating it to match an ambitious goal. Inventory and hiring are sized to the inflated number, and when actual demand lands far below, the business is left with excess stock and overcapacity. Rebuilding the practice, the team forecasts from real pipeline and historical conversion rates, states its assumptions, presents a range instead of a single number, and tracks forecast accuracy each period to improve the model. Decisions now rest on an honest estimate with known uncertainty, so resourcing matches reality. The lesson: a forecast bent to match a wish stops being a forecast — its value comes from being an honest, measurable prediction, not a flattering target. (Illustrative; RGM analysis.)
Failure modes to watch. Bending the forecast to match a desired target instead of predicting honestly; presenting a single number as certain rather than a range with assumptions; never tracking forecast accuracy against actuals to improve; using a method mismatched to the horizon or data; and ignoring seasonality or known upcoming changes.

Synonyms & antonyms

Synonyms

projectionpredictionestimate

Antonyms

actualshindsightguess

Origin & history

"Forecast" comes from Middle English forecasten, "to plan beforehand, contrive" (fore- "before" + casten "to cast, reckon"). The sense moved from contriving in advance to projecting or reckoning future conditions, keeping the core idea of casting an estimate forward in time.

Etymology: source.

Usage trends

Search interest for this term over the last five years:

View interest-over-time on Google Trends →

Common questions

What is a forecast?
A data-based prediction of future values — such as sales, demand, or revenue — built from historical data and explicit assumptions, used to guide planning, budgeting, and resourcing.
Is forecast a noun or a verb?
Both. As a noun it is the prediction itself. As a verb, to forecast is to predict or estimate a future value (past tense usually 'forecast', sometimes 'forecasted').
How do you make a forecast more reliable?
State your assumptions, present a range rather than false precision, use a method matched to the horizon and data, and track forecast accuracy against actuals each period so the model improves over time.

Resources & people to follow

Curated, non-competitor resources verified per term.

Related training

Disciplines

Areas of marketing where forecast is a core concern:

Sources

  1. trendsGoogle Trends — "sales forecast"