Free tools · Cost to serve · Runs in your browser

Modven Whale Curve Builder

A whale curve sorts customers from most to least profitable and plots cumulative profit. It usually rises above 100 percent of total profit, then falls as unprofitable customers are added. The height of the hump is the profit your worst customers are destroying. Paste one row per customer with revenue, gross margin, and cost to serve, or use the sample, and the builder draws the curve and reports the numbers that matter. Nothing leaves your browser.

Sample data · 80 made-up customers

One row per customer

customer,revenue,gross_margin,cost_to_serve
Customer 001,22030,7246,2212
Customer 002,227291,62410,35950
Customer 003,246777,68110,60671
Customer 004,300626,70311,38949
Customer 005,205612,42674,35862
Customer 006,421547,131960,60243
Customer 007,422582,125249,109371
Customer 008,407740,133399,49050
Customer 009,320920,79112,27596
Customer 010,86778,20938,32488
Customer 011,227219,73369,24707
Customer 012,132457,35927,10651
Customer 013,403811,83865,31203
Customer 014,184637,60821,45595
Customer 015,80659,19334,7965
Customer 016,63846,17521,13491
Customer 017,400626,105804,171574
Customer 018,167698,45660,41400
Customer 019,445357,113807,88239
Customer 020,144055,35882,14199
Customer 021,280158,90451,55138
Customer 022,28247,7258,1734
Customer 023,533843,123211,91580
Customer 024,95105,26915,17789
Customer 025,373476,121260,226391
Customer 026,251603,60022,19456
Customer 027,28094,5625,4328
Customer 028,236021,63374,48888
Customer 029,370526,86304,55851
Customer 030,32170,8638,5671
Customer 031,169090,55647,36172
Customer 032,40216,13497,12199
Customer 033,51641,11939,5757
Customer 034,26043,8014,7327
Customer 035,108467,22190,14635
Customer 036,33471,9917,10744
Customer 037,371771,119187,227511
Customer 038,254646,65888,37150
Customer 039,370678,94805,38154
Customer 040,376379,104719,53486
Customer 041,231343,57119,81707
Customer 042,41590,10133,19706
Customer 043,166659,53682,66007
Customer 044,173631,38017,18198
Customer 045,260012,86430,25374
Customer 046,91981,20535,17589
Customer 047,132836,35991,49531
Customer 048,243486,49584,23346
Customer 049,42143,12694,4035
Customer 050,181794,47282,27728
Customer 051,306561,100602,167282
Customer 052,473753,96423,153403
Customer 053,223445,72787,19505
Customer 054,28477,6127,1254
Customer 055,152685,50753,13542
Customer 056,42070,12389,5305
Customer 057,530015,137361,128062
Customer 058,78435,20260,6383
Customer 059,291980,98225,65100
Customer 060,112186,24356,12210
Customer 061,38013,8018,4196
Customer 062,130554,34896,39004
Customer 063,82697,20180,4098
Customer 064,82709,17600,11652
Customer 065,265102,81373,51059
Customer 066,479175,149567,130370
Customer 067,67085,17240,7713
Customer 068,135369,40752,36263
Customer 069,227003,73510,142567
Customer 070,89482,23998,46258
Customer 071,69208,14609,9369
Customer 072,212525,64466,113351
Customer 073,42729,9971,11404
Customer 074,412416,128684,117545
Customer 075,122369,32064,49925
Customer 076,360713,85807,71237
Customer 077,77985,17644,13576
Customer 078,390933,123178,66692
Customer 079,364986,78921,52124
Customer 080,22119,4832,1019

Columns: customer, revenue, gross_margin, cost_to_serve. Or customer and profit. Paste from Excel or upload a CSV.

Upload CSV

Peak of the curve

187%

of total profit, reached by your top 63 of 80 customers

Customers losing money

17 of 80

Profit they destroy

$639K

Build it from your records →

How it works

Every number, and where it comes from.

Customer profit

Gross margin minus cost to serve, for each customer. If you only have profit, a single profit column works too.

The curve

Customers sorted from most to least profitable, with cumulative profit as a share of total profit.

Peak

The highest point of the curve: the profit you would have if the customers after the peak cost nothing.

Profit destroyed

The sum of losses from customers with negative profit.

↓ Customer template (CSV)customer, revenue, gross_margin, cost_to_serve

Questions

Asked often, answered plainly.

What is a whale curve?

A chart of cumulative profit with customers sorted from most to least profitable. It was popularized in management accounting research on customer profitability¹⁷.

How do I estimate cost to serve?

Start with four drivers priced from your own costs: orders, order lines, deliveries, and returns. Add payment terms and sales time if you can. A consistent method matters more than precision.

Is my data uploaded?

No. The file is read and charted in your browser and never sent anywhere.

17Kaplan, R. S. & Narayanan, V. G. (2001). Measuring and managing customer profitability. Journal of Cost Management, 15(5), 5–15.

How to find out which customers actually make you money →How to find the freight your business pays for and never bills →

Where this shows up

Cost to serve · Industrial MRO distribution

Small-order cost to serve in industrial MRO distribution. Small orders are how we keep the big accounts. They pay for themselves.

Cost to serve · Foodservice distribution

Split cases and drop size in foodservice distribution. Our independents are our best margin. Every stop is worth making.

Inventory · Fastener distribution

VMI and bin program margins in fastener distribution. Our VMI programs are our stickiest and most profitable business.

Start here

Where do you suspect the value is hiding? Tell us your hunch. Ten days later it comes back with numbers on it.

10 business days · $500, credited against any build