How to Monetize Your API Product

The API Economy

APIs are products. Whether you're providing data, AI capabilities, infrastructure services, or developer tools, your API has value—and customers will pay for it.

Monetizing an API requires:

API Pricing Models

Freemium

Free tier with limited access, paid tiers for more.

Free: 100 requests/day, 1 req/second

Starter: 10,000 req/day, 10 req/second $29/month

Pro: 100,000 req/day, 50 req/second $99/month

Business: 1,000,000 req/day, 100 req/second $499/month

Best for: APIs with a clear value escalation (more calls = more value). Most developer-facing APIs.

Usage-Based (Pay As You Go)

Charge per API call, per unit of data, or per compute unit.

$0.001 per request (first 100K free)

$0.01 per MB of data processed

$0.05 per AI inference

Best for: APIs where usage varies wildly between customers. AI/ML APIs, data processing.

Tiered Subscriptions

Monthly plans with different feature access and rate limits.

Starter ($29/mo): Basic endpoints, 1,000 req/day

Pro ($99/mo): All endpoints, 50,000 req/day, batch API

Business ($299/mo): Dedicated support, 500K req/day, webhooks, SLA

Best for: APIs where features differ by tier (not just volume). B2B API products.

Hybrid

Base subscription plus usage charges beyond included amounts.

Pro ($99/mo): Includes 50,000 requests

$0.002 per additional request

Best for: Balancing predictable revenue with fair usage-based pricing.

Implementation with StackBE

1. Set Up Plans with Entitlements

Define plans with entitlements that map to API capabilities:

Plan: Starter ($29/month)

Entitlements:

Plan: Pro ($99/month)

Entitlements:

2. API Key Authentication

Use StackBE's API key system for customer authentication:

// Your API middleware

async function authenticateRequest(req, res, next) {

const apiKey = req.headers['x-api-key'];

if (!apiKey) {

return res.status(401).json({ error: 'API key required' });

}

// Validate key and get customer context

const session = await stackbe.auth.validateApiKey(apiKey);

if (!session) {

return res.status(401).json({ error: 'Invalid API key' });

}

req.customer = session.customer;

req.subscription = session.subscription;

next();

}

3. Usage Tracking

Track every API call for billing and analytics:

async function trackUsage(req, res, next) {

// Track the API call

await stackbe.usage.track(req.customer.id, 'api_calls');

// Check if within limits

const { hasAccess, current, limit } = await stackbe.entitlements.checkLimit(

req.customer.id,

'daily_requests'

);

if (!hasAccess) {

return res.status(429).json({

error: 'Daily request limit exceeded',

current,

limit,

upgradeUrl: 'https://yourapi.com/pricing'

});

}

next();

}

4. Feature Gating

Restrict endpoints by plan:

async function requireFeature(feature) {

return async (req, res, next) => {

const { hasAccess } = await stackbe.entitlements.check(

req.customer.id,

feature

);

if (!hasAccess) {

return res.status(403).json({

error: `${feature} requires a higher plan`,

upgradeUrl: 'https://yourapi.com/pricing'

});

}

next();

};

}

// Usage

app.post('/api/v1/batch', requireFeature('batch_api'), batchHandler);

app.post('/api/v1/webhooks', requireFeature('webhooks'), webhookHandler);

5. Rate Limiting

Enforce per-second rate limits based on plan:

const rateLimit = require('express-rate-limit');

function planBasedRateLimit(req) {

const plan = req.subscription?.plan?.slug;

const limits = {

starter: 1, // 1 req/second

pro: 10, // 10 req/second

business: 100, // 100 req/second

};

return limits[plan] || 1;

}

app.use('/api/', rateLimit({

windowMs: 1000,

max: planBasedRateLimit,

standardHeaders: true,

legacyHeaders: false,

}));

API Product Best Practices

Documentation is Marketing

Your API docs are the first thing developers evaluate. Invest in:

Developer Onboarding

Make it easy to start:

1. Sign up → get API key instantly

2. Free tier with enough requests to evaluate

3. Copy-paste code examples

4. Sandbox environment for testing

Transparent Pricing

Developers hate pricing surprises. Be clear about:

Usage Dashboard

Give customers visibility into their consumption:

Versioning

API versions are important for paid products:

Customer Self-Service

API Key Management

Customers should be able to:

Subscription Management

Using StackBE's customer portal or your own UI:

Monitoring and Analytics

Track metrics for your API business:

StackBE's analytics provide subscription-level metrics. Pair with API monitoring (Datadog, New Relic) for technical metrics.

Example: AI API Product

A common pattern—monetizing an AI/ML model via API:

Free Tier:

Pro ($49/month):

Enterprise ($299/month):

StackBE manages the subscriptions and entitlements. Your API server handles the actual inference.

Next Steps

1. Define your pricing model: Start with tiered subscriptions

2. Set up StackBE: Create plans with usage-based entitlements

3. Implement API key auth: Authenticate and identify customers

4. Add usage tracking: Meter every API call

5. Build rate limiting: Enforce plan limits

6. Create documentation: Make your API easy to adopt

7. Launch with a free tier: Lower the barrier to entry