GFT instruments / Digital product development
In the illustrative example, digital development saves USD 96,000 a year and 23 calendar days per style. Test the retained physical rounds, fees and approval clock against your own evidence.
An instrument for the decision
Start with a stated assumption
Annual cost difference / current B
of physical-only cost saved
Digital development saves cost and calendar time under these assumptions. Test whether the retained physical round achieves the required approval.
23 calendar days saved per style. This is a sampling-stage opportunity, not a committed launch date.
Hold a scenario still
A holds the cautious preset until you save your own. Change the inputs above and current B moves against it. B minus A is signed.
| Annual cost or per-style clock | Saved A | Current B | B minus A |
|---|---|---|---|
| Physical annual cost | USD 270,000 | USD 270,000 | USD 0 |
| Digital annual cost | USD 289,000 | USD 174,000 | USD -115,000 |
| Annual saving | USD -19,000 | USD 96,000 | +USD 115,000 |
| Calendar days saved per style | 4 days | 23 days | +19 days |
Bars show the sign of B minus A. Sage means B is better than A and ochre means worse; for costs, lower is better. Each row has its own scale.
Read the calculation
Nine terms, one ledger. Hover or tap a term on the plate and every place it acts lights up in the live result.
Physical = S × N × R × C
Each block is one physical round: N samples a style at C each, across S styles.
Digital = S × (D + N × K × C) + H
Saving = S × N × (R − K) × C − S × D − H
Clock: R × L against T + K × L
23 days a style. Not a committed launch date, and not additive across styles.
Break-even = ⌈ H ÷ (N × (R − K) × C − D) ⌉
Contribution per style: USD 210 a style. Your volume: 500 styles a year.
01 / 05
Let S be annual styles, N samples in each physical round, R physical-only rounds and C the loaded cost of one sample. Physical = S × N × R × C. The same N and C apply on both routes; a different specification needs its own scenario.
With the current inputs: USD 270,000 a year, physical-only.
02 / 05
Let K be the physical rounds kept after digital review, D the total 3D fee per style and H annual digital overhead. Digital = S × (D + N × K × C) + H. Retained rounds may be zero only where the buyer accepts it.
03 / 05
Saving = S × N × (R − K) × C − S × D − H. Avoided physical cost, less fees, less overhead.
04 / 05
Physical elapsed time is R × L. Digital is T + K × L, where T is all digital work and approval per style. Samples in a round run together, and styles do not multiply the clock. The result is a sampling-stage opportunity, conditional on the route being sequential.
05 / 05
Per-style contribution is N × (R − K) × C − D. When positive, the break-even volume is H divided by it, rounded up. At zero styles the overhead is still payable, and a percentage saving is undefined when physical cost is zero.
Compare to your inputs
Your calculator inputs match the default, so the saving is USD 96,000 a year. Change an input and the gap to the default shows here.
| Input | Default | Cautious | Effect of +10% on saving | Status and basis |
|---|---|---|---|---|
| 500 styles/year | 500 styles/year | +USD 10,500 | Illustrative. Example annual development workload. | |
| 2 samples/style/round | 2 samples/style/round | +USD 18,000 | Illustrative. Two garments in each physical approval package. | |
| 3 rounds/style | 3 rounds/style | +USD 27,000 | Illustrative. Example sequential approval cycle. | |
| 90 USD/sample | 90 USD/sample | +USD 18,000 | Illustrative. Example material, labour and allocated courier cost. | |
| 14 calendar days/round | 14 calendar days/round | +USD 0 | Illustrative. Example making, transit and review interval. | |
| 150 USD/style | 200 USD/style | -USD 7,500 | Illustrative. Example all-in 3D modelling and revision fee. | |
| 5 calendar days/style | 10 calendar days/style | +USD 0 | Illustrative. Example total time before physical confirmation. | |
| 1 rounds/style | 2 rounds/style | -USD 9,000 | Illustrative. Example retained confirmation round, not a guaranteed reduction. | |
| 9,000 USD/year | 9,000 USD/year | -USD 900 | Illustrative. Example licence, training and equipment allowance, entered annually. |
Sage bars to the right raise the saving; ochre bars to the left lower it. The cautious preset retains more physical work and raises digital effort. The small-portfolio preset changes only volume and keeps the same annual overhead.
Use the result with care
A saving counts only as far as each gate holds. Scroll through the four gates a sample must pass before the round is counted as saved.
Hold the specification
The saving rests on a sample that still exists on file. Evidence to hold: the specification and the physical sample it was drawn from.
Hold the fit sign-off
Evidence to hold: fit and construction accepted by an authorised reviewer, recorded against the revision.
Hold the buyer acceptance
Evidence to hold: the buyer accepts the digital approval, kept beside each sample revision.
Count the avoided spend
Counted only if every earlier gate holds.
avoided physical cost a year, under the current inputs.
01 / 04
A garment drawing is not evidence that a buyer will accept a digital approval. Keep physical confirmation rounds in the plan until an authorised reviewer has accepted the route.
02 / 04
Fit, construction, handle, colour and buyer sign-off can each need different evidence. The wireframe control changes the illustration only. It does not change rounds, cost or quality.
03 / 04
Capture the start and end of each event: making, shipping, feedback queues and correction. If work runs in parallel, replace the sequential clock with an observed critical path. Never add displayed days across styles.
Sequential events, illustrative and not to scale. Replace each with an observed number of days.
04 / 04
Separate avoided spend from released capacity: salaried sample-room time that is redeployed is not cash saved. Put licence, training and equipment in annual overhead without double counting the per-style fee.
CountedAvoided sample spend
Not countedRedeployed sample-room time
Annual overheadLicence, training, equipment
What the model leaves out
Select comparable styles, record actual invoices and time stamps, and keep buyer acceptance beside each revision. No carbon, water or waste saving can be inferred from the cost difference. A negative saving or a slower clock is a useful result: it shows where fees, complexity or retained approvals consume the benefit.
Sources and next decisions
Saving = S × N × (R − K) × C − S × D − H
Choose a source below and the terms it can help you evidence light up. Or point at a term to find the readings that touch it.
Browzwear's product overview, opened on 30 October 2026, describes garment simulation using physical fabric data. It gives qualitative context for the digital route. A vendor description is not independent evidence of achievable savings, so no vendor percentage, price or development time is used. The source-open register is available as JSON.
Digital sampling and on-demand production. In the GFT commissioning register, in preparation: not a claim that a released PDF is available here.
The move from generated images to technical specifications. In the GFT commissioning register, in preparation: not a claim that a released PDF is available here.
The records needed before any optimisation. In the GFT commissioning register, in preparation: not a claim that a released PDF is available here.
Live from the calculator
Physical annual cost = styles × samples per round × physical rounds × cost per sample. Digital annual cost = styles × (3D fee per style + samples per round × retained physical rounds × sample cost) + annual overhead. Savings reconcile to avoided physical cost minus 3D fees and overhead. Elapsed days are sequential, per style.
Method source: GFT arithmetic from explicitly illustrative user assumptions. Browzwear provides qualitative context only; no vendor performance percentage is used.
A planning aid. Not investment, legal or tax advice. Verify inputs and boundaries before an operational decision.
Close the loop
Keep physical confirmation in the plan until fit, drape, construction and buyer approval are evidenced. This instrument measures an assumed development route; it does not certify garment quality or predict sales.
Planning rule, illustrative: each item not yet evidenced keeps one more physical round in the plan, up to the physical-only rounds.
Saved round / Provisional
a year only if all 3 items are evidenced.
With the evidence so far, plan on USD 6,000 saved a year.
Physical rounds kept2
The saved round, under the evidence ticked above
Avoided cost, current inputsProvisional until every item is tickedLocked in
Record actual sample invoices, courier allocations, digital revision effort, calendar time and first physical approval. Replace the illustrative inputs with measured observations from comparable styles before committing a wider development budget.
Approvals confirmed
2 of 3 so far
Plan on USD 6,000 saved a year.