Channel & Marketplace Profitability Calculator

Purpose and model boundary

This calculator shows what is left from each sale on each sales channel. A seller sells up to 10 products through up to 3 channels, over a plan of 1 to 12 months. Each product on each channel is one sales row, with its own price, discount, monthly units, returns, ads and inventory. Up to 15 fee rules belong to the channels. A monthly pattern scales the units of every row.

One Calculate fills every result section of that one model: the plan by channel, product and row, a fee audit, cash by month, the break-even price of one product on each channel, the price for a target margin when you enter one, 100 simulated return levels and an 11 by 11 what-if table of price against returns.

Every figure on this page is computed by the spreadsheet; the page adds nothing to it. Every value is your own assumption. The calculator holds no channel's fee schedule, it does not say how customers respond to a price or how a channel will change its terms, it is not certified financial reporting, and it does not guarantee a profit.

Inputs and units

• Plan: the months in the plan, a whole number from 1 to 12, and the channel the others are compared against, chosen from the channel IDs you typed.
• Products, up to 10 rows, filled from the top without a blank row between used rows: a product ID, which is a capital letter and then up to 15 capital letters or digits, each ID used once; the product cost per unit, from 0 to 100,000; and optionally the share of that cost you keep when a unit comes back and can be resold, from 0% to 100% (blank means 0%). Channel fees and shipping do not belong in the product cost; enter them as fee rules and profiles, so they are counted once. At least one product is required.
• Channels, up to 3 rows, filled from the top: a channel ID, in the same form; the payment delay in whole months, from 0 to 6 (blank means 0); and the storage cost per unit per month, from 0 to 1,000 (blank means 0). At least one channel is required.
• Fulfilment profiles, up to 10 rows, which may be empty: a profile ID, and the pick and pack cost per order, the shipping cost per order and the return shipping cost per returned unit, each from 0 to 10,000 (blank means 0).
• Sales by product and channel, up to 30 rows, filled from the top. Rows can be typed or pasted from a spreadsheet. Each row has a product and a channel from their tables, one row per product and channel; a list price from 0 to 100,000; and units a month, either 0 or from 0.01 to 100,000. List price times units a month must be at most 1,000,000,000. Optional, with what blank means: the discount, from 0% to 100% (0%); units per order, from 1 to 10,000 (1); the shipping charged per order, from 0 to 10,000 (0); the return rate, from 0% to 100% (0%); a fulfilment profile from its table (no fulfilment cost); the ad spend a month, from 0 to 10,000,000 (0); and the average inventory in units, from 0 to 10,000,000 (0). At least one row is required.
• Fee rules, up to 15 rows, which may be empty. Rows can be typed or pasted from a spreadsheet. Each rule has a rule ID, used once; a channel from its table; and what it is charged on: Item sales, Shipping, Combined, Orders or Units. Optional, with what blank means: a percent, from 0% to 100% (0%), which a rule on Orders or Units cannot have; a fixed amount, from 0 to 10,000 (0); a minimum and a cap, each from 0 to 10,000 with the cap not below the minimum (none); the refund on returns, from 0% to 100% (not refundable); and the first and last month, from 1 to 12 (the whole plan). A rule on Item sales, Shipping or Combined also says whether it is charged per order or per item.
• Monthly sales pattern: a sales index for each of the 12 months, either 0 or from 0.01 to 5. Blank means 1. Months after the plan are not read.
• Price search: the product to price, chosen from the product IDs you typed, and optionally the lowest and highest list price to try, each from 0 to 300,000. The slider reaches 10,000; you can type a higher price in the box. Blank lowest means 0, and blank highest means 3 times the product's highest list price. The two may be equal: the searches then test that one price.
• What-if table: a price multiplier from 0 to 3 and a return multiplier from 0 to 5, applied to every row before anything is calculated (1 unless you change them), and the spacing of the table's rows, above 0 up to 0.2, and columns, above 0 up to 1.
• Optional, under "Optional: target and risk":
  • the target margin, from −100% to 95% (blank means no target search);
  • the simulated return multiplier low, most likely and high, each from 0 to 5, in that order (0.8, 1 and 1.2 by default);
  • the random seed, a whole number from 1 to 2,147,483,646 (blank means 42).

Money is in dollars. Percentages are shares of a price, of an amount or of units.

Governing relationships

Units and orders. Units on a row over the plan are units a month times the sum of the sales index over the months in the plan. Orders are units divided by units per order. Units, orders and returned units are expected values, so they can be fractions.

A fee rule. A rule applies to every sales row of its channel. Per order or per item, in the rule's own months, the amount before limits is the percent of what the rule is charged on, plus the fixed amount. Item sales means the price after discount, Shipping means the shipping charged and Combined means both; Orders and Units take the fixed amount only. The minimum and cap then hold that amount, per order or per item, on the original amount. The fee is that amount times the orders or items sold in the rule's months. The refund is the returned share of the original fee times the refund on returns, including any fixed part.

The ledger. Each line of each row is rounded once to the cent, half away from zero. Every total is a sum of those lines.

• Net revenue is item sales plus shipping collected less refunds. Refunds are the returned units at the price after discount; shipping collected is not refunded.
• Net product cost is the product cost of all units less the returned stock kept, which is the returned units at product cost times the share kept.
• Net fees are the fees charged less the fee refunds.
• Fulfilment is orders times pick and pack plus shipping out. Return shipping is returned units times its rate.
• Ads are the ad spend a month times the months in the plan.
• Storage is average inventory times the channel's storage rate times the months in the plan. It comes from inventory, never from sales, so it carries on through a month with no sales.
• Contribution is net revenue less net product cost, net fees, fulfilment, return shipping, ads and storage.

Margin is contribution divided by net revenue, and contribution per unit is contribution divided by units. Each is blank when what it divides by is zero. The best channel has the highest contribution, and a tie goes to the earlier row. The best channel per unit is read to 15 digits: two channels that match that far tie, and the earlier row is named.

Cash by month. Cash is separate from contribution. Costs fall in the month they happen. Customer money and fees settle after the channel's payment delay, so some money can land after the plan ends: that amount is shown. Sales, cost of sales and fees spread over the months by the sales index, and a fee only over its own months. Ads and storage spread evenly. Each channel's months add up exactly to its contribution, with any rounding cent placed by month order. Product cost is dated in the month of sale; stock purchases are not modelled.

Break-even and target prices. For the product to price, on each channel it sells on, the search varies that row's list price, before its own discount, and every other row keeps its price. It tries 101 evenly spaced prices from the lowest to the highest, and where the goal is crossed it narrows the price by 40 halving steps. The break-even goal is a contribution of zero and always runs. The target goal is contribution equal to your margin on net revenue and runs only when you enter a target. The answer is the lowest price that meets the goal, within one cent of contribution. A price rounded up to the cent is shown beside it. When the goal is already met at the lowest price tried, that price is the answer, with a warning. Fee minimums and caps can make margin move both ways with price, and the page warns when they do: prices closer together than one scan step can then be missed. Up to 3 crossings are located and reported; a falling crossing too steep to locate within a cent is counted but not reported.

Simulation. Each of the 100 trials draws one return multiplier from your low, most likely and high (a triangular distribution). That one number scales the returns of every row and channel, so channels are compared on the same draws. Prices stay fixed and nothing is re-optimized. Each trial is exact, because contribution moves in a straight line with the return rate. The same seed and inputs give the same 100 trials, and each Calculate after the first moves on to the next seed, so a new press draws new trials. Percentiles from 100 trials are illustrative only, and 0 of 100 trials below zero does not mean zero risk.

Return multiple at break-even. For each channel, the channel table shows how many times current returns would take its contribution to zero. It is blank when returns cannot do so, or when some row would pass 100% returned first.

What-if table. Rows are 11 price multipliers centred on yours, one row step apart; columns are 11 return multipliers centred on yours, one column step apart. Each cell is the total contribution recalculated by an Excel Data Table. The middle cell is your own plan. When a step would take the lowest row or column below 0, or take a row's returns above 100%, the table is withheld with that reason and every other result still stands.

Calculation sequence

The spreadsheet first checks the products, channels, profiles, sales rows, fee rules and monthly pattern, then that each key names a row of its table, then the settings, and stops with NOT VALID at the first problem it finds, with every figure at 0. It then works out each rule's fee on each row and posts the ledger to the cent, adds the channel, product and rule totals, and dates the cash. It searches the prices, runs the 100 trials and recalculates the what-if table at its 121 combinations. A block of consistency checks runs before the status is returned, including that the rows and channels add up to the plan, that each channel's cash adds up to its contribution, that the fee audit adds up to the net fees, and that the table's middle cell equals the contribution.

Outputs and interpretation

The headline gives the total contribution, the margin and the cash that arrives within the plan. The result sections follow.

• The plan: the best channel, its lead and the best channel per unit, the contribution per unit, the units, returned units and orders, each revenue and cost line and how many rows lose money; with tables by channel, by product and by sales row. The channel table also shows each channel against the one you chose to compare with, its cash in and after the plan, and its return multiple at break-even.
• Fee audit: the fees charged, refunded and net; and for each rule its months in the plan, the rows it charged, the orders or items charged, its fee, refunds and net, and how many rows sit at its minimum and at its cap. The audit adds up exactly to the fees in the plan.
• Cash by month: the amount after the plan, the largest cash need and its month; with net cash by channel, the whole plan and the running total, month by month.
• Break-even price on each channel: the range searched; and for each channel the price now, the status, the lowest price, that price rounded up to the cent and after the discount, the contribution and margin there, whether the answer is the lowest price tried, the crossings and prices found, and the closest the scan came.
• Price for the target margin: the same table for your target. With no target entered this section is empty and says so.
• Risk: 100 simulated return levels: the mean, median, 10th and 90th percentile, lowest and highest total contribution; the share of trials below zero with its count and standard error; the means of the first and last 50 trials and the seed used; with a table by channel, including how often each channel was best, and a histogram.

For nearby questions, the Cost-to-Serve & Minimum Profitable Order Calculator looks at what one order costs by size and policy, the Price Volume Profit Scenario Simulator projects profit over months when demand responds to price, and the Quote Pricing & Deal Margin Optimizer prices one deal.

Validation and status logic

The workbook returns one status, chosen in this order: NOT VALID, then INFEASIBLE, then NO SOLUTION FOUND, then CHECK, then OK.

• NOT VALID names the first problem: a product, channel, profile, sales row or fee rule (a blank row above a used row, a missing, malformed or repeated ID, a value outside its limits, or a rule that does not fit together, such as a percent on Orders or a minimum above the cap); no product, channel or sales row; a month index outside its limits; a sales row or rule naming a product, channel or profile not in its table, or a product and channel entered twice; a setting outside its limits, including a return rate that a multiplier would take above 100%; or a calculation that exceeds the supported numerical range.
• INFEASIBLE means the lowest price to try is above the highest after a blank highest takes its value. The plan, cash, fee audit, simulation and table stay valid and shown.
• NO SOLUTION FOUND means no price in the range brings a searched row to break-even or, with a target entered, to the target margin. The plan, cash, fee audit, simulation and table stay valid and shown. A channel that reached its goal keeps its answer, and the closest the scan came is shown for the one that did not.
• CHECK accompanies a valid result that needs a look because a workbook consistency check failed.
• OK otherwise.

Warnings say when sales rows lose money; when the channel to compare against has no sales rows; when a goal is already met at the lowest price tried; when margin does not move one way with price on a searched row; when the search found more than 3 crossings; when no row has returns, or no row has both sales and a price, so what-if columns or rows are identical; when the simulated multipliers are all equal; when a month index after the plan is not used; when the what-if table is withheld; when net revenue is zero on a selling channel; when the product to price has no sales rows; when an amount settles after the plan; and when a fee rule charges nothing on this plan.

Assumptions and limitations

• Capacities are 10 products, 3 channels, 10 profiles, 30 sales rows, 15 fee rules and 12 months, with cash shown to month 18.
• Units are what you enter. A price or fee change moves no units: the calculator does not estimate how customers respond.
• One return multiplier is shared by every row and channel in a trial, so the simulation does not show one channel's returns moving on their own.
• Returned units are refunded at the price after discount. Shipping collected is not refunded. A returned unit keeps only the share of cost you enter.
• A fee rule applies to every sales row of its channel. Its limits apply per order or per item, not per month or per plan.
• Stock purchases, taxes, overheads and financing costs are not modelled.
• A row at the largest allowed size can leave a target search that is negative without an answer, because 40 halving steps then resolve price more coarsely than one cent. It reports no solution, never a false price.
• Above about $10 trillion of revenue plus cost the calculator refuses, because whole cents stop being exact there. When only some what-if scenarios pass that limit, only the table is withheld.
• Results exactly on, or within rounding noise of, a half-cent edge may differ by one cent, including a tie between channels or the month a cent of cash falls in, so the best channel or peak month named can change.
• Amounts within two cents below the $10 trillion limit may show as $10 trillion. Near $10 trillion, this can also change the peak month or raise a one-cent settlement warning.
• Near $10 trillion, whether a plan with returns simulation is refused can depend on the seed, because it refuses only when a drawn trial exceeds the limit.
• Above $10 billion, a simulated mean can be off by less than one cent.
• A loss far under a cent can read as no loss, and near $10 trillion two channels less than 0.05 of a cent apart in a trial count as tied.

Restrictions and non-computing states

The calculator enforces its numeric and choice limits before it accepts a result. A blank row between used rows, a repeated ID, a key not in its table, a sales row above the size limit and a fee rule that does not fit together are refused by the workbook. With no target the target section is left blank. When a table step would take the what-if table out of range, only the table is withheld.

Errors and warnings

A request rejected by the page's input limits is not a computed result. A transport or service failure, a timeout or a cancelled run cannot establish a fresh workbook answer, and the last result stays on the page marked as out of date. Review the workbook's References and Disclaimer, and check a result against your own costs and your channels' current terms, before using it to set a price or choose a channel.

Sources and further reading

Your prices, units, costs, fee rules, returns, ads, inventory and payment delays come from the inputs; the calculator holds no market, channel or fee data, and every value is your own assumption. The sources below explain the ideas the model uses. They do not endorse this calculator.

• OpenStax, Principles of Accounting, Volume 2: Managerial Accounting, 3.1 Explain Contribution Margin defines contribution margin as the amount by which a selling price exceeds variable cost, the amount left to cover fixed costs and profit; the calculator's contribution is a channel's net revenue less the costs its sales cause (retrieved 2026-11-03).
• OpenStax, Principles of Accounting, Volume 2: Managerial Accounting, 3.2 Calculate a Break-Even Point in Units and Dollars explains the break-even point as the level at which costs are recovered; the calculator searches for it by price on each channel rather than by a formula, because fee minimums and caps bend the line (retrieved 2026-11-03).
• Microsoft Support, Calculate multiple results by using a data table describes the two-variable data table the spreadsheet uses for the 11 by 11 what-if table (retrieved 2026-11-02).
• Park, S. K. and Miller, K. W. (1988), Random number generators: good ones are hard to find, Communications of the ACM 31(10) describes the multiplicative congruential generator with modulus 2^31 − 1 that draws the simulation's return multipliers (DOI checked 2026-11-02).

This is an educational model of the plan you enter, not financial, accounting, pricing or legal advice. It does not estimate how customers respond to a price or how a channel will change its fees, it is not certified financial reporting, and it does not guarantee a profit; check a result against your own costs and your channels' current terms before using it.