Your margin is lying.

Right product. Right quantity. Right price. Right time. Right on.

Fluff is for puffers, not purchase orders.

Buy planning for optimized fashion brands. Small team, serious numbers: see what to order, what it really costs to land and the margin you keep, before you sign the PO, not after. Built to scale from your first drop to your fiftieth.

Work with a planner

Free in your browser. OptiSKU models the numbers you enter. It doesn't predict a bestseller.

  • Lean buys: fewer styles, bought deeper
  • Mean margins: priced from what it lands at, not what the factory said
  • No fluff: every term in plain English, no buying degree
  • Built for the AI age: factory and PO emails, written with your numbers
OptiSKU™

Season plan

$0
Open-to-buy at cost: what this season's stock will cost you
Margin Units Styles SKUs

Sales target

$

What you expect to bill this season across every channel, after discounts.

Channels

Share of sales. The three always add to 100%.

Categories

Each category's share of sales. Shares rebalance to 100%. Styles are set automatically from your MOQ; use − and + to override.

Price tiers

Split every category into good, better and best price points. Each tier gets its own styles, SKUs and PO lines.

Start from last season

Plan the way seasoned buyers do: start from the same season last year, what sold and how much of the buy it cleared. Enter last season's sales and sell-through for each category. Leave a row blank if it's new.

The State of Fashion 2026 report expects the overall market to grow only in the low single digits. Bigger growth needs a reason.
    Planning rules
    The share of stock you expect to sell at any price, markdowns included. Wholesale is bought by the store, so it counts as sold. For context, The Business of Fashion and McKinsey's State of Fashion 2021 reported that before the pandemic only about 60% of garments sold at full price; the rest sold on markdown or didn't sell.
    Shared with Color Studio.
    Comes off the open-to-buy.
    Drops
    Separate launches within the season.
    Leave at $0 for a first season. Used to check that the target's growth is realistic.
    Keep part of the open-to-buy uncommitted until early sales show which styles are working. The Timeline tab shows whether a reorder can land in time.

    The plan

      Assortment review

      Each category's share of sales against its share of the open-to-buy. When a category takes more of your cash than it brings back in sales, it's working harder for less.

      Share of salesShare of open-to-buy

        Drops

        A starting plan built from the rules above, not a forecast. Prices and costs come from each garment's example numbers and likely HTS duty; open a category on the Price tab to set your real ones, and the plan updates.

        Your factory just said “MOQ 500.”

        You said “sounds good.” You have no idea what that means.

        We should talk.

        OptiSKUYou make the product.
        We'll teach you the math.

        Big ideas
        require
        better math

        $16 FOB sounds cheap.

        Then it gets on a boat. Then off a boat. Then meets customs. Then meets your warehouse.

        Your $16 would like you to meet landed cost.

        OptiSKUYou make the product.
        We'll teach you the math.

        You paid $20. You sell it for $40.

        Congratulations on your 50% margin.

        Unless that $20 was FOB. Add freight and duty and you're closer to 38%.*

        *Assumes $1.60 a unit of freight and 16.5% duty, the US base rate for a cotton knit tee, on a $20 FOB. Added tariffs take it lower.

        OptiSKUYou make the product.
        We'll teach you the math.

        You ordered
        50 XS
        50 S
        50 M
        50 L
        50 XL
        50 XXL

        because the MOQ was 300.
        Why? No idea.
        Correct.

        OptiSKUYou make the product.
        We'll teach you the math.

        “We did $100K!”

        Amazing. Now tell us your gross margin, markdown rate, sell-through, inventory on hand and returns.

        Still amazing? Now we know.

        OptiSKUYou make the product.
        We'll teach you the math.

        It's a
        business now
        (nice)

        Keep more of every sale.

        Margin is what's left of the price after the product, shipping, duty, fees and discounts. Most of it is decided before you place the order. Here are five places it leaks, and where OptiSKU catches each one.

        1. 01

          Price from what it costs to land, not the factory price.

          A $20 tee from the factory is closer to $24.90 once freight and duty are paid. Sell it at $40 and you keep 38%, not the 50% you counted on.

        2. 02

          Buy the sizes people actually buy.

          An even split leaves the smallest and largest sizes on the shelf, and whatever's left on the shelf ends up on sale.

        3. 03

          Fewer colors, bought deeper.

          Every color has a factory minimum. Too many colors means small runs, surcharges, and leftovers in the shades nobody picked.

        4. 04

          Plan the discount before you need it.

          Sell a 60%-margin piece at 15% off and you keep about 53%. Know how deep you can cut before a sale starts costing you money.

        5. 05

          Don't let a late sample force air freight.

          Air often costs five to ten times ocean per piece. Most rush shipping starts with a sample that slipped weeks earlier.

        Work with a planner

        Stuck on a number? Get a second pair of eyes.

        Ideally ones that have read a cost sheet before.

        The free tools take you most of the way. When you want a person to check your plan before you sign the PO, book a session with an OptiSKU planner: 15+ years in production, merchandising, SKU planning and international licensing at premium apparel brands.

        1 hour · video call

        Plan check

        $250

        • Your landed cost and real margin, line by line
        • MOQs: what to push back on and what to accept
        • Size split and color count for your first order
        • A short written summary after the call

        3 hours · two calls

        Season plan

        $1,000

        • A full buy plan for your next drop: styles, colors, sizes, units
        • Pricing for DTC and wholesale from real landed cost
        • Factory timeline worked back from your launch date
        • Your plan saved in OptiSKU to keep updating

        Move the number. See the impact.

        Every screen answers one question a founder asks before placing an order. Change an input and every number that depends on it changes with it.

        Plan

        Type a sales goal, pick what you sell and where you sell it, and get the season: how much to spend on stock, how many styles and colors, every size of every color checked against your factory minimums, the dates, the cash you'll need, and draft orders to confirm with each factory.

        Landed

        Pick from 111 products, from tees and polos to puffers, loafers and jewelry, and OptiSKU fills in its likely customs code and import duty. Add shipping, tariffs and fees to see what each piece really costs to land, the margin you'll keep, and how much you need to sell to get your cash back.

        Size

        Turn one MOQ into a size run that matches how your customers buy. See the sales you'd miss and the stock you'd sit on with an even split.

        Color

        Plan the color story, pull colors from published runway trend palettes and Pinterest's reported 2026 search trends, then split the buy by your own weights or past sales. Anything under the factory's color minimum gets flagged.

        Compare

        Save a version at $60 and another at $68. Try 300 units against 500. Keep the buy that makes sense and show it to your partner, investor or factory.

        Track

        Once you launch, enter what sold each week. OptiSKU shows where every category is heading and tells you what to do next: reorder the winners, hold your price, or discount, and by how much.

        Ask AI

        Built for the AI age. Get your factory email and PO email written with your real numbers in seconds, or have AI pressure-test your plan and price. OptiSKU writes the prompt with your numbers in it. Paste it into ChatGPT, Claude or any AI you use.

        Live

        Follow one style from tech pack to sell-through on a little road, with a walking tee that keeps pace with your dates. Tick each stop as it happens. Late samples, POs under MOQ, factory holidays and launch slips get flagged before they cost you a selling week.

        From design to customer.

        Follow one garment from sketch to checkout. Every stop shows how long it takes, what it adds to the cost, and the words your factory, forwarder and stores will use.

        Shipping
        Sold through

          Who pays for what

          Incoterms are the shipping terms on your quote. They decide where the factory's job ends and yours begins. FOB is the most common term on factory quotes. FOB and CIF are sea-freight terms; air quotes use FCA and CIP instead.

          Costs use the garment's example numbers and likely HTS duty from the app; change them on the Price tab and this page follows. Duty codes and rates are planning guesses, not rulings; confirm with a licensed customs broker.

          Jargon, translated.

          The words your factory, forwarder and stores use, in plain English, with what each one does to your margin. The same list is in the app: tap Words at the top of any screen.

          Margin
          What you keep from the price after the cost of the product, as a share of the price. Sell for $100, cost $40: 60% margin.
          This is the number to protect. Everything else on this list feeds it.
          Markup
          How much you add on top of cost, as a share of the cost. Cost $40, sell for $100: 150% markup. That's the same deal as a 60% margin.
          Mixing up markup and margin is the most common pricing mistake. A 50% markup is only a 33% margin.
          IMU (initial markup)
          The margin built into your full prices before any markdowns, discounts or shrink, as a share of the full price. Want to keep 55% and expect 15% in reductions? (55 + 15) ÷ (100 + 15) = 61% IMU, so a style that lands at $40 needs a full price of about $102.
          Set it higher than the margin you want to end with, because reductions take some back. A 61% IMU is about a 156% markup on cost.
          Landed cost
          Everything to get one unit into your warehouse: FOB, freight, duty and tariffs.
          The cost your margin should be worked out from.
          MOQ
          Minimum order quantity: the fewest units a factory will make, per style or per color.
          Ordering under it usually means a surcharge per piece.
          FOB price
          Free on board: the factory's price to make the goods and load them at its port. After that, the cost and risk are yours.
          Only part of your cost. Price from landed cost instead.
          SKU
          Stock keeping unit: one size of one color of one style. A tee in 3 colors and 6 sizes is 18 SKUs.
          Every SKU needs its own stock. Lots of thin ones means leftovers you end up discounting.
          Open-to-buy
          How much you can spend on stock this season, after counting the stock you own and what's already on order.
          Spend past it and the extra usually leaves as markdowns.
          Sell-through
          The share of the stock you bought that actually sold. Buy 100, sell 70: 70% sell-through.
          Every unsold piece is cost with no sale to pay for it.
          Markdown
          A price cut to clear stock. It comes straight out of your margin.
          A 20% markdown on a 60%-margin piece leaves 50%.
          Wholesale
          Selling to stores at a discount, usually about half of the retail price, so they can make their own margin.
          Less margin per piece, but bigger orders and no customers to find.
          Keystone
          Pricing at twice your cost. Stores often keystone your wholesale price to set retail.
          Keystone wholesale leaves you about half the retail price to cover cost and margin.
          3PL
          Third-party logistics: an outside warehouse that stores, packs and ships your orders.
          Added tariffs
          Extra duties on top of the base rate, such as Section 301 tariffs, that depend on where goods are made.
          Where it's made can change your margin by several points.
          AQL inspection
          A quality check that samples finished goods against an agreed defect limit before you pay the balance.
          Balance
          The rest of the payment, usually due when the goods ship or 30 days after.
          Bill of lading
          The shipping document that proves what was loaded and who can collect it.
          Break-even
          The point where sales cover every cost. Below it you lose money; above it you make some.
          CBM
          Cubic meter, the unit ocean freight is priced in. A 20-foot container holds about 28 CBM of cartons; a 40-foot about 58.
          Color minimum
          The fewest units the factory or mill will dye in one color.
          Under it, mills add a surcharge or won't dye the color.
          Colorway
          One color version of a style.
          Commission
          The marketplace's share of each sale.
          Price for it, or it comes out of your margin.
          Critical path
          The list of dates, worked back from launch, that every step has to hit.
          Customs broker
          A CBP-licensed agent who files your import entry. You, as importer of record, still owe the duty, and formal entries need a customs bond.
          DDP
          Delivered duty paid: the factory's price includes shipping and duty to your door.
          Easy, but you pay for the convenience inside the price.
          Deposit
          Money paid when you place the PO, often 30%, so the factory can buy fabric.
          Cash out months before any sale comes in.
          Direct to consumer (DTC)
          Selling through your own site or stores.
          You keep the full price, minus payment fees and any discounts.
          Drop
          A batch of new styles that launch together.
          More drops keep things fresh, but each one is another set of orders and minimums.
          Duty
          The import tax, charged as a percentage of the goods' customs value. In the US that's usually what you paid the factory (roughly FOB); the EU and UK also add freight and insurance.
          Comes out of your margin unless it's in your price.
          Ex-factory
          The date the goods leave the factory. Most deadlines are set against it.
          EXW
          Ex works: you collect at the factory door and handle everything after that.
          FCL
          Full container load: you book a whole 20- or 40-foot container for a flat price. Cheaper per unit once you fill most of it, and it goes straight from factory to you.
          Fit sample
          A sample in your base size to correct fit. Most styles need two or three rounds.
          Freight forwarder
          The company that books space on ships or planes and handles the paperwork for you.
          GMROI
          Gross margin return on inventory: how many dollars of margin each dollar of stock earned.
          Higher means your stock is working harder for its cost.
          Gross margin
          What's left of sales after the cost of the goods you sold, as a share of sales. Sales $100, landed cost of those units $40: gross margin is $60, or 60%. Here it's also after payment fees and commissions.
          After payment fees and commissions, this is what pays for everything else.
          Gross profit
          Sales minus the cost of the goods you sold, in dollars rather than as a percentage.
          HTS code
          The tariff code that classifies your product and sets its duty rate.
          Importer of record
          The party legally responsible for the import, usually your company.
          Incoterms
          Shipping terms like FOB or DDP that decide where the factory's job ends and yours begins. FOB and CIF are for sea freight; air uses FCA and CIP.
          Inventory turn
          How many times you sell through your average stock in a period.
          Higher means less cash sitting on shelves.
          Lab dip
          A swatch of fabric dyed to match your color, for approval before bulk fabric is dyed.
          LCL
          Less than container load: you share a container with other shippers and pay by volume (CBM). Cheaper for small shipments, but it adds about a week to pack and unpack the shared box, and more handling.
          Fine for small runs. Past about 18 CBM, two-thirds of a 20-foot container, a full container is usually cheaper.
          Lead time
          How long from placing the order to having the goods. For most clothing by sea it's often three to five months from PO to warehouse, plus two to three months of sampling before that.
          Short on time means paying for air freight or rush fees.
          Line sheet
          The catalog you send stores: every style with colors, sizes, wholesale price, retail price and delivery dates.
          Marketplace
          A site that sells your product for you and takes a commission on each sale.
          The commission comes straight out of your margin, so price for it.
          MSRP
          Manufacturer's suggested retail price: what you ask stores to sell at.
          Net 30
          Payment due 30 days after the invoice or delivery.
          Peak cash
          The most money you'll be out of pocket, after paying the factory and before sales pay you back.
          PO
          Purchase order: your official order, with styles, colors, sizes, prices and dates.
          PP sample
          Pre-production sample in the real fabric and trims, approved before cutting starts.
          Proto sample
          The first sample made from your tech pack, to check the idea before you fix fit and fabric.
          Reorder (chase)
          Ordering more of a style that's selling fast.
          Holding some budget back lets you chase the winners instead of discounting the losers.
          Size curve
          How your units are split across sizes, based on what people actually buy.
          The right curve means fewer leftovers in the smallest and largest sizes.
          Stock-to-sales
          Stock at the start of a month divided by that month's sales. 3 means you're holding three times what you'll sell.
          Style
          One design, in all of its colors and sizes.
          Tech pack
          The instructions for a style: sketches, measurements, materials, stitching and labels. The factory quotes and samples from it.
          TOP sample
          Top of production: a sample pulled from the bulk run to confirm it matches what you approved.
          Weeks of supply
          How many weeks your stock will last at the current rate of sales.

          Want the formulas and worked examples? Read the guides to landed cost, MOQ, margin vs markup, size curves, sell-through and IMU.

          TheOptiSKUIndex

          Twice a year we'll survey independent brands on what they pay, charge and sell through, by category and price point, and read it against public trend reports. Results are published only as totals, never by brand. Join the list to take part and get the first issue.

          • Pricing
          • Assortment
          • Sell-through
          • Markdowns
          • Inventory
          • Trends

          We'll email you to confirm. You'll get product news and the Index, and you can unsubscribe any time. See Privacy.

          FreeEvery card and the full planner for founders.
          StudioFor brands running full seasons. Pricing at launch.
          White-labelFor retailers and agencies, on request.

          40 cards. Always free.

          Pricing, wholesale, cost, margin, quantity, inventory and cash. Each card answers one question with your numbers and says what the answer means.

          Further readingThe books and research behind the math

          OptiSKU's math comes from the books merchandisers learn on and the research the industry reads. Here's where each idea in the app comes from, if you want to go deeper. For duty rates, tariffs and customs rules, see all sources.

          Retail math and buying

          The arithmetic and the six-month plan that every buying course teaches.

          Mathematics for Retail Buying

          Bette K. Tepper · Fairchild Books

          The standard on markup, margin, open-to-buy and markdown math.

          In OptiSKU: The Fashion Math cards, initial markup and open-to-buy.

          Retail Buying: From Basics to Fashion

          Richard Clodfelter · Fairchild Books

          The buyer's job end to end, from the six-month plan to vendor negotiation.

          In OptiSKU: The six-month plan in Plan › Timeline.

          Merchandise Buying and Management

          John Donnellan · Fairchild Books

          Planning and controlling inventory from a merchant's point of view.

          In OptiSKU: Stock-to-sales ratios and the stock plan.

          Retailing Management

          Michael Levy, Barton Weitz and Dhruv Grewal · McGraw-Hill

          The broad retail text, with strong chapters on merchandise planning systems.

          In OptiSKU: GMROI and inventory turn in the plan totals.

          Buying and merchandising, the UK way

          How UK retailers split the buyer and merchandiser roles and run the season week by week.

          Fashion Buying

          Helen Goworek · Blackwell (now Wiley)

          The fashion buyer's year, from range planning to sourcing.

          In OptiSKU: Critical-path dates and POs.

          Analytics and inventory

          How data changes the way assortments and inventory are planned.

          The New Science of Retailing

          Marshall Fisher and Ananth Raman · Harvard Business Review Press

          Forecasting, reading early sales, markdowns and assortment, from Wharton and Harvard Business School.

          In OptiSKU: The reorder reserve and the tracker's chase, hold and markdown calls.

          Industry research

          The yearly read on where fashion is heading.

          The State of Fashion

          The Business of Fashion and McKinsey & Company · published every year

          The most widely read annual report on the fashion industry, built from executive surveys and market data. The 2026 edition expects the industry to grow only in the low single digits again, and names tariffs, AI and resale among its ten themes. The 2021 edition argued that brands make too much and range too wide: it reported that only about 60% of garments sold at full price before the pandemic, and that long tails of unproductive SKUs drag on profit.

          In OptiSKU: the long-tail check on your SKU list, the growth check against last season, and the full-price benchmark next to sell-through.

          Read it at The Business of Fashion or McKinsey & Company.

          Book links search WorldCat for libraries and editions near you. OptiSKU isn't affiliated with these authors or publishers. Benchmarks from The State of Fashion are as reported by The Business of Fashion and McKinsey & Company and press coverage of the reports.

          The Season Trail · a game

          You have died of inventory.

          One hero product, from moodboard to markdown. Survive the sample round, the big buy, a jammed port and Black Friday. Can you make it to spring?

          Good products.
          Better math.

          Great product doesn't sell itself. A beautiful hoodie at a bad margin is still a bad margin. Keep the creative energy and make smarter decisions around it.