Buying tool screens on a deep green field: an assortment mix chart, an Incremental sales opportunity card reading $9,488 to 9,978 with 75 to 79 additional units needed, 24.3 to 24.9 per cent missed opportunity and a recommendation; the Assortment Builder table listing A-line, Pleated, Body con, Fit and flare, Mini, Knitted and Shirt dress against year-on-year change, forecast volatility and WGSN market mix; and an SKU panel pricing a flared skater at £90, a mini skater at £120 and a cashmere mini skater at £180

Fashion Buying Tools

Combining a buyer's own sales data with WGSN's forecast to plan assortments and size trends with confidence

The problem

Buyers plan four seasons at once, against a critical path that runs 6–8 months out. They have no shortage of data — but no single source they trust. Sales data is the only thing they believe. Everything else is "finger in the wind": a wide range, no way to back it up.

Role

Research

Design direction

Design (design discovery)

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Research

We interviewed buyers and merchandisers globally to understand their day-in-the-life, and where WGSN could sit inside a workflow that's currently Excel, comp shopping, and instinct.

What came back, again and again:

Time is the enemy. Four seasons running concurrently, a calendar of meetings, no room to read a long report.
Numbers are the only currency. Qualitative insight — even from field reps — gets discounted. "I'm not gonna change my whole assortment based on what one sales manager is telling me."
The tools don't talk to each other. Excel, PDFs retyped by hand, disconnected systems for one answer.
WGSN was being used, but thinly — mostly pre-season, mostly by seniors shaping strategy, rarely by the buyer doing the day-to-day range build.

The proposition

Buyers trust their own sales data above all else — but it only looks backwards. Combine that history with WGSN's forecast, and you get something buyers don't have anywhere else: a bespoke buying plan, not a generic trend report. Capitalise on your assortments — forecasts and analysis on which trends to adopt, and the optimal point in their lifecycle, so buyers can invest with confidence.

The Assortment Builder plan screen: Dresses A/W 25/26, tagged Women, Apparel, Early adopter and UK/EMEA, above a table of items — Skater, A-line, Pleated, Body con, Fit and flare, Mini, Knitted and Shirt dress — each showing year-on-year change, forecast volatility, WGSN market mix, the buyer's own A/W 24/25 sales mix, a buying recommendation of Maintain Position, Aggressive Increase or Decrease, and the resulting A/W 25/26 buy mix, both mix columns totalling 100 per cent — Assortment Builder

Two Assortment Builder input screens: Build your assortment, explaining how WGSN's algorithm forecasts trends and how the buyer's data is kept, with market and department options beneath; and an SKU panel for Skater — an A/W 25/26 buy mix of 14 per cent, up 3.2 per cent year on year — with a carry-over field and a search across WGSN original CADs returning line drawings of skater dresses — Assortment Builder

What we built

Four concepts were prototyped and tested — Assortment Builder, Opportunity Calculator, Pitch Notes, and a buyer-facing Dashboard — all tied together by the same idea: WGSN's forecast, calibrated against the buyer's own numbers. Of those, two were taken forward and shipped:

Assortment Builder — plans the ideal mix for a season by combining past-season sales with WGSN's forecast. Replaces the manual range-plan buyers were rebuilding from scratch every season.
Opportunity Calculator — sizes a trend the moment a buyer spots it: how much to back it, in dollars, using an AI-driven forecast calibrated to their own sales.

The Opportunity Calculator result for Jackets, Blazer, US, 1.1. to 31.3.25: a planned assortment mix of 15.7 per cent against a WGSN recommended average of 19.6 per cent, a 3.9 per cent difference, and an assortment mix chart; alongside an Incremental sales opportunity panel reading $9,488, 79 additional units needed and 24.6 per cent missed opportunity, with a recommendation to increase the mix by 24.6 per cent and Harrington and Anorak listed as other high movers to calculate — Opportunity Calculator

Two Opportunity Calculator input screens: Calculate your opportunity, explaining how the calculation combines the buyer's sales data with WGSN's trend forecast, with forecast and hindsight calculation options and market and department pickers; and the form beside it — target customer, region, date range, category, item, average selling price and planned assortment mix — Opportunity Calculator

Feedback

What buyers said about the two tools that shipped — the Assortment Builder and the Opportunity Calculator:

"You've probably saved me about a week of my life every season."

"I would ask our company to please purchase this for all of the buyers."

"This would absolutely make me more confident in making buying decisions."