Free API monetization calculator

Compare markup, packages and prepaid credits on the same usage

Name: UsageBox
Author: UsageBox

Enter your measured variable cost and monthly usage, then compare three common monetization shapes without coupling the calculation to one provider or billing platform.

Open the calculator See the architecture

Three models, one measured fact

Cost-plus markup
Subscription with included usage + overage
Prepaid credit packs
No provider pricing table to go stale

Workload economics

Measured units / monthYour variable cost / 1,000 units

Use whatever stable quantity you actually measure: requests, tasks, tool calls, token bundles or another numeric unit. The calculator does not assume one billing unit.

Cost-plus

Markup on measured cost

Package + overage

Monthly package

Included unitsOverage / 1k

Prepaid packs

Pack price

Units per pack

Measured variable cost

$150

for 100,000 measured units this month

Highest modeled gross margin

Subscription + overage: 33.0%

This is arithmetic, not a recommendation. Packages and prepaid packs concentrate variance and breakage differently from cost-plus pricing. Model the distribution, not just one average customer.

Pricing model	Monthly revenue	Variable cost	Gross profit	Gross margin	Effective price / 1k units
Cost-plus / markup 30% markup on measured variable cost	$195	$150	$45.00	23.1%	$1.95
Subscription + overage $99.00 includes 50,000 units, then $2.50/1k	$224	$150	$74.00	33.0%	$2.24
Prepaid credit packs 4 × $49.00 packs at 25,000 units/pack	$196	$150	$46.00	23.5%	$1.96

Not included: payment processing, taxes, support, fixed infrastructure, refunds, discounts, credit expiry/breakage or customer acquisition cost. Prepaid credits also require a real ledger with drawdown/expiry policy; UsageBox does not own that ledger.

When pricing leaves the spreadsheet

Keep the measured quantity stable while pricing changes

Cost-plus, packages and credits can all sit on the same underlying usage fact. UsageBox keeps that quantity retry-safe and independently auditable; your application or billing system applies the commercial model.

See the monetization architecture Preview the usage request Start free →

Metered unit ≠ billed unit

You can measure requests or tasks while selling credits or packages. Keeping measurement separate is what lets packaging change without rewriting every producer.

Average margin can hide whales

A profitable average customer does not make a flat package safe. Repeat the math at p50, p90 and p99 usage before setting included allowances.

Credits need their own ledger

Pack economics are easy; expiry, drawdown order, late events and refunds are not. Keep those commercial rules downstream from the usage meter.