Collection Planning Calculator

This calculator adds up your fashion collection's four production phases — sampling, production, shipping, and a buffer — into a single Total Lead Time in weeks, then reverse-engineers two milestone dates from that sum. The Design Deadline is simply the full lead time itself, since finalized designs are what every downstream phase depends on; count backward that many weeks from your target delivery date to know when sketches must be locked. The Production Order Deadline drops the sampling phase from the total (production + shipping + buffer only), representing the moment you must place the bulk order — sampling is treated as already complete by then.

Critical Path strips out the buffer weeks entirely, showing sampling + production + shipping as the bare minimum sequential timeline if absolutely nothing goes wrong; compare it to Total Lead Time to see how much slack your buffer is actually buying you. Note that Number of Styles is captured as an input for context but doesn't change the math here — a 5-style capsule and a 200-style full collection get the same deadlines for a given set of phase durations, since sampling and production weeks are assumed to already account for however many styles you're running. The biggest planning trap is treating these phases as compressible in parallel: this model assumes sampling, production, and shipping are strictly sequential (you can't ship until production is done, and can't produce until samples are approved), which matches how most cut-and-sew supply chains actually work but overstates timelines for brands with parallel-track vendors.