• Planners spending most of each week manually adjusting system forecasts because the model doesn't account for promotions, seasonality, or known demand events?

  • Safety stock levels set by gut feel or outdated rules of thumb, leaving the business either over-stocked on slow movers or regularly out of stock on fast movers?

Demand Forecasting Software Development

Off-the-shelf planning platforms cover demand forecasting for standard product ranges and predictable demand patterns. Custom becomes the right choice when your product mix, seasonality structure, promotional calendar, or supplier lead time variability means the platform's default models produce forecasts that require significant manual adjustment before they are usable.

We build demand forecasting systems designed around your planning cycle -- your SKU structure, your replenishment lead times, your seasonal peaks, and the exception management workflow your planning team relies on to catch problems before they become stockouts or overstock positions.

  • Statistical forecasting models -- moving average, exponential smoothing, seasonal decomposition -- selected and tuned per SKU based on demand history and variability

  • Seasonal adjustment capturing recurring demand patterns so forecasts reflect actual peaks and troughs rather than a flat trend line

  • Safety stock calculation based on lead time variability, demand variability, and target service levels -- recalculated automatically as inputs change

  • Replenishment suggestions generated from the forecast, safety stock position, and current inventory, with planner approval before order creation

RaftLabs builds custom demand forecasting software for supply chain and operations teams who need statistical forecasting, seasonal adjustment, safety stock calculation, replenishment suggestions, and forecast accuracy tracking in one connected system. Most demand forecasting projects deliver in 10 to 14 weeks at a fixed, agreed cost.

Vodafone
Aldi
Nike
Microsoft
Heineken
Cisco
Calorgas
Energia Rewards
GE
Bank of America
T-Mobile
Valero
Techstars
East Ventures
100+Software products shipped
FixedCost delivery
10-14Week delivery cycles
24+Industries served

When spreadsheet forecasting stops scaling with your business

Most supply chain teams start forecasting in spreadsheets. For a small, stable product range, a well-maintained spreadsheet works. The problems appear as the range grows, as the business adds channels with different demand patterns, as promotional activity becomes more frequent, and as leadership asks for forecast accuracy reporting that the spreadsheet cannot produce without significant manual effort. Planners spend more time maintaining the model than improving the forecast. New SKUs take weeks to onboard into the planning process. Seasonal adjustments are applied inconsistently across the range. And when a planner leaves, the institutional knowledge embedded in the spreadsheet leaves with them.

We build demand forecasting systems for manufacturers, distributors, and retailers managing product ranges where demand variability, lead time uncertainty, and seasonal patterns make spreadsheet planning impractical. The forecasting model -- which statistical method fits each SKU, how promotions and events are captured, how safety stock is calculated, and how replenishment suggestions are generated -- is designed during discovery before any code is written.

What we build

Statistical forecasting engine

Forecasting models selected per SKU based on demand history length, variability, and pattern -- simple moving average for stable low-volume lines, exponential smoothing for lines with trend, seasonal decomposition for lines with clear annual or weekly cycles, and ensemble methods that combine multiple models where no single approach dominates. Model selection running automatically when a new SKU is onboarded and re-evaluated periodically as demand history accumulates. Forecast horizon configurable to match your supplier lead times -- a 4-week forecast for short-lead suppliers, a 12-week forecast where lead times require earlier commitment. Confidence intervals alongside each point forecast so planners can see the range of likely outcomes rather than a single number that implies false precision. Historical back-testing showing how each model would have performed on past data so the model selection rationale is visible and auditable.

Seasonal adjustment and event capture

Seasonal index calculation from demand history, identifying recurring uplift and depression patterns by week, month, or quarter and applying them to the baseline forecast automatically. Promotional calendar integration so planned promotions, price changes, and product launches are captured before the event and their demand impact estimated from comparable historical promotions. Event library storing the demand impact of past events -- a specific retailer promotion, an annual trade show, a product recall -- so the impact can be applied to future events of the same type without manual estimation each time. Seasonal profile management per product category, channel, and region where seasonality differs across the business. Override capture recording every manual adjustment a planner makes, with the reason noted, so the adjustments are visible in forecast accuracy reporting and can inform model improvement.

Safety stock calculation

Safety stock calculated per SKU from three inputs: demand variability over the replenishment lead time, lead time variability from supplier data, and target service level set by the planning team per product category. Calculation updated automatically when any input changes -- when lead time data shows a supplier's performance has deteriorated, or when a service level target is revised. Multiple service level targets supported so higher-margin or higher-criticality lines carry more safety stock than lower-priority lines without the planning team managing this manually. Safety stock recommendations presented with the calculation inputs visible so planners can see why the recommendation changed and challenge the inputs if they believe the data is wrong. Historical service level tracking showing actual fill rate against target so the relationship between safety stock setting and service outcome is visible over time.

Replenishment suggestions

Replenishment order suggestions generated from the forecast demand, safety stock position, current on-hand inventory, and in-transit stock already ordered -- the suggested order quantity reflecting what is genuinely needed rather than a round number or a minimum order quantity applied without context. Order suggestions grouped by supplier so the planning team can review and approve all lines for a supplier in one step rather than processing individual SKU suggestions separately. Minimum order quantity and order multiple rules applied to each suggestion automatically, with the rounding impact shown so planners can decide whether to round up, round down, or negotiate an exception. Approval workflow capturing the planner's decision on each suggestion -- approve, modify, or defer -- before the order is created. Integration with your ERP or purchasing system so approved replenishment suggestions create purchase orders directly without re-keying.

Forecast accuracy tracking

Forecast accuracy measured at the SKU and aggregate level using MAPE, WMAPE, and bias metrics -- the metrics your operations and finance teams are likely already reporting or want to start reporting. Accuracy reported at multiple levels: by SKU, by product category, by planner, by supplier, and at the total business level, so the planning manager can see where accuracy is strong and where it needs attention. Bias tracking identifying whether the forecast consistently over-predicts or under-predicts specific SKUs or categories, which signals a systematic model problem rather than random error. Accuracy trend over time showing whether the forecasting process is improving, stable, or deteriorating -- particularly useful after model changes, process changes, or significant demand disruptions. Accuracy benchmarking against the previous period and against industry reference points where relevant.

Exception management

Exception alerts surfacing the SKUs and situations that require planner attention: forecast accuracy below threshold, safety stock below minimum, replenishment suggestion above a set order value, lead time extension flagged by the supplier, or a slow-mover building excess stock beyond a weeks-of-cover limit. Exception queue showing all active exceptions prioritised by impact -- the exceptions that represent the largest stock risk or the largest cost exposure presented first. Exception resolution workflow capturing the planner's response to each exception and the action taken so the exception record is complete and auditable. Configurable exception thresholds per product category so the rules that trigger an exception for a high-value fast mover differ from the rules for a low-value slow mover. Exception trend reporting showing which exception types recur most frequently so the planning team can address root causes rather than treating recurring exceptions as routine.

Frequently asked questions

ERP planning modules handle standard reorder point and min/max replenishment well. Custom is right when your SKU range has enough variability in demand patterns that a single forecasting method produces poor results across the range, when your promotional and event calendar materially affects demand and the ERP module can't model it cleanly, when you need forecast accuracy reporting that the ERP doesn't produce, or when the exception management workflow your planning team needs doesn't match what the module offers. We'll tell you honestly if configuring your existing ERP planning module would cover the requirement.

At minimum, two to three years of sales history at the SKU and location level, a product master with categorisation and unit of measure, and a supplier master with lead times. Promotional history, if available, significantly improves forecast quality for businesses with an active promotional calendar. Inventory on-hand and in-transit data is needed to generate replenishment suggestions. We'll assess what you have during discovery and tell you what can be built with your available data versus what becomes possible as more data accumulates.

Yes. Common integrations include SAP, Microsoft Dynamics, NetSuite, and major WMS platforms. The integration covers pulling sales history and inventory positions into the forecasting system and pushing approved replenishment suggestions back as purchase order requests. The integration spec is documented before development starts so you know exactly what data moves where and when.

A focused build covering statistical forecasting, seasonal adjustment, safety stock calculation, and replenishment suggestions typically runs $35,000 to $70,000 depending on the number of forecasting models required and the complexity of the replenishment logic. Adding forecast accuracy dashboards, exception management workflows, and ERP integration typically brings the total to $70,000 to $130,000. Fixed cost agreed before development starts, no hourly billing.

Related supply chain software

Talk to us about your demand forecasting project.

Tell us how your team forecasts today -- your product range, your planning cycle, and where the current process lets you down. We'll scope a forecasting system built around your actual demand patterns and replenishment requirements.