credit-based-billing

Dodo Payments Credit-Based Billing

Use this skill to build prepaid or included-credit billing for tokens, API calls, compute, storage, or currency-denominated value, with auditable grants and deductions.

When to use this skill

• Include a recurring credit allowance in a subscription.
• Sell one-time top-up packs or prepaid usage.
• Deduct credits from metered AI, API, or compute consumption.
• Grant promotional or support credits and record a reason.
• Configure expiry, rollover, low-balance alerts, or overage.
• Reconcile a customer's balance against an immutable ledger trail.

Choose the billing model

Credit-based and usage-based billing are complementary. Define and test meters with the usage-based-billing skill; this skill covers the credit side and the meter-to-credit link.

Core concepts

Credit entitlements and grants

A credit entitlement is the reusable definition of a credit unit and its lifecycle: name, unit, precision, expiry, rollover, and overage. A grant is an issuance of that credit to one customer. Grants can originate from:

• a subscription, reissued each billing cycle;
• a one-time product or add-on;
• a direct API ledger credit;
• rollover from an earlier grant.

Credits gate how much a customer can consume. The separate entitlements resource gates fulfillment such as feature access, files, or license delivery. Do not confuse these SDK namespaces:

client.creditEntitlements             credit definitions and balances
client.creditEntitlements.balances    customer credit balances and ledger
client.entitlements                   feature/file/license entitlements
client.entitlements.files             entitlement files
client.entitlements.grants            fulfillment grants

Use client.customers.listCreditEntitlements(customerID) for the customer-level credit-entitlement view. Do not substitute client.customers.listEntitlements(...), which reads the other entitlement system.

Custom-unit and fiat credits

Custom-unit precision is configurable from 0 through 10; the dashboard default is 2. Precision cannot be changed after creation, so choose it before issuing grants. Use 0 for indivisible units such as whole requests. Use decimal precision only when fractional credits are meaningful.

Fiat examples use currency minor units: 5,000 credits represents USD 50 in the documented OpenAI example. Do not infer a universal fiat precision rule beyond the documented minor-unit model. All monetary amounts are in the currency's smallest unit (for example, cents for USD).

A product can carry up to five credit entitlements. Each can have independent issuance and lifecycle settings.

Balance and ledger

The balance response includes balance, overage, last_transaction_at, identifiers, and timestamps. Treat credit amounts as decimal strings; do not pass them through binary floating-point arithmetic.

Every transaction has a ledger record with:

• balance_before and balance_after;
• overage_before and overage_after;
• amount and transaction type;
• source references and grant ID;
• description, metadata, and timestamp.

This ledger is the audit trail and provides transaction-level balance snapshots. There is no separately documented historical balance-snapshots endpoint.

Initialize the TypeScript SDK

Keep API keys server-side. Dodo Payments keys use dodo_test_... and dodo_live_... prefixes.

import DodoPayments from 'dodopayments';
 

The SDK defaults to live_mode when environment is omitted. Use test_mode explicitly during development.

Create and configure a credit entitlement

The confirmed TypeScript method is client.creditEntitlements.create(...).

price_per_unit is a decimal string in the configured currency; monetary values use the currency's smallest unit. In this example, '1' is one cent per overage credit for USD.

Confirmed create options

Configure rollover

Rollover carries eligible unused credits into a new grant. Configure:

1. rollover_enabled: true.
2. rollover_percentage as the carry-forward cap from 0 through 100.
3. Both rollover_timeframe_count and rollover_timeframe_interval; neither should be supplied alone.
4. max_rollover_count if credits may roll only a limited number of consecutive times.

Rollover is applied before expiry; only the remainder expires.

Configure expiry

The API represents expiry as nullable expires_after_days. The dashboard offers 7, 30, 60, 90, custom days, or never; its default is 30 days, and custom expiry has a one-day minimum. Use null for no API-configured expiry only where the current API form permits it.

Configure overage

When overage_enabled is true, price_per_unit is required; when a price is present, currency is required. Use overage_limit to cap allowed overage units.

When overage is disabled, Dodo stops deducting after the balance reaches zero. Meter processing is asynchronous, so this is not synchronous authorization for your application requests. Implement application-side enforcement when requests must be rejected immediately.

Attach credits to products and subscriptions

Credits are attached to products as credit entitlements in the product creation or edit flow. Do not use client.entitlements.grants to attach or issue credit balances.

Subscription product

In Products → Create Product or an existing product:

1. Choose subscription pricing.
2. Open Entitlements & Credits and attach an existing credit entitlement.
3. Set the credits issued each billing period.
4. Optionally set a low-balance notification amount, trial-credit amount, whether unused trial credits expire after trial, and credit proration for plan changes.
5. Keep the entitlement's default rollover, overage, and expiry rules or customize them for this product.

The customer receives a fresh grant each billing cycle.

One-time product or add-on

Attach the credit entitlement to a single-payment product or add-on and configure the one-time amount. The purchase issues one grant. This is the supported shape for prepaid packs, top-ups, and promotional bundles.

Usage-based product

Attach the credit entitlement to the same usage-based product as the meter. The confirmed meter attachment fields are:

Product attachment request shapes can evolve. Configure them in the dashboard or copy the current schema from the Create Product API; do not invent an entitlements, credits, or grants payload.

Start checkout for an attached product

Product purchase creates the customer grant; checkout does not accept an ad hoc credit amount.

Use checkoutSessions.create, not the deprecated payments.create or subscriptions.create methods.

Discover a customer's credit entitlements

Use the customer resource when the application needs to discover all credit entitlements associated with a customer:

Use the balance resource below when the credit entitlement ID is already known and an exact balance is required.

Read a customer's balance

The confirmed method takes the customer ID first and the credit entitlement ID inside the options object:

balance and overage are decimal strings in the entitlement's credit unit. They are not currency amounts unless the entitlement itself represents fiat value.

Grant credits manually

Manual credits are appropriate for promotions, migrations, refunds implemented as credit, and support gestures. Use a stable idempotency key derived from the business operation so a retry cannot grant twice.

amount is a decimal string backed by NUMERIC(38,28); its integer part must be below 10^10. expires_at applies to credits. Keep the amount within the entitlement's configured precision.

If the same idempotency_key already exists, the API can return 409. Treat that as a signal to reconcile the original operation, not as permission to generate a new key and retry the grant.

Deduct credits manually

Use the same method with entry_type: 'debit'. Debits consume the earliest-expiring grants first and can return 400 when the balance is insufficient.

Do not manually debit usage that is also connected to automatic meter-to-credit deduction; that charges the same consumption twice.

Read the ledger for an audit trail

The SDK returns an auto-paginating iterable:

Persist the Dodo ledger entry ID with internal order, support-case, or job IDs. Reconciliation should compare ledger entries and source references rather than overwrite history from a cached balance.

Configure automatic meter-to-credit deduction

1. Attach a credit entitlement to the usage-based product.
2. Add the meter to the same product.
3. Enable Bill usage in Credits for that meter.
4. Set credit_entitlement_id and meter_units_per_credit.
5. Ingest events whose case-sensitive event_name matches the meter.

A background worker processes new usage approximately every minute, aggregates it according to the meter, converts meter units using meter_units_per_credit, and deducts from non-expired grants with the earliest-expiring grants consumed first. There is no free threshold on a credit-billed meter. Multiple meters can consume one shared credit pool at different conversion rates.

This delay is material: an accepted usage event does not imply that a balance read immediately afterward includes its deduction.

Use the usage-based-billing skill to create the meter, choose count, sum, max, or last, define its filter, and validate event batching and metadata.

End-to-end AI token example

Full guide: references/ai-token-example.md.

Handle credit webhooks

Full guide: references/credit-webhooks.md.

Covers:

• Low-balance payload
• Low-balance notification flow

Enforce credits safely

Best-effort balance gate

For a precision-0 entitlement, a server can perform a coarse pre-check with integer-safe parsing:

Use this only for precision 0. For fractional credits, use an arbitrary-precision decimal implementation that preserves the entitlement's configured precision.

This read is not a reservation. Two concurrent requests can both observe enough balance, and automatic meter deductions may not yet be reflected.

Strict request enforcement

Choose one of these patterns:

• Predictable fixed cost: create an idempotent manual debit before serving. Treat an insufficient-balance 400 as denial. If work fails after debit, issue a separately idempotent compensating credit with a linked reason. Do not also meter the same usage.
• Variable cost such as AI tokens: reserve estimated capacity atomically in your own datastore, enforce per-customer concurrency, ingest actual usage afterward, and reconcile local reservations with Dodo webhooks and ledger entries.
• Overage product: authorize against the product's overage policy and your own risk limit, not merely balance > 0.

Return an application-level payment/credit-required response with a top-up or upgrade path when authorization fails. Do not expose Dodo API errors or secrets to the client.

Race conditions to avoid

• Check then act: a remote balance read followed by work is not atomic.
• Immediate post-event read: the meter worker may not have processed the event.
• Parallel workers: multiple jobs can consume the same apparent balance without a local reservation or atomic debit.
• Retry with new IDs: changing event_id or idempotency_key after a timeout can duplicate usage or adjustments.
• Cache as authority: webhook-maintained balances are useful for display, not strict authorization.
• Mixed deduction paths: automatic meter deduction plus manual debit double-counts consumption.

Common mistakes

1. Confusing two resources. creditEntitlements and entitlements are different. Credit balances do not live under client.entitlements.grants.
2. Calling invented balance methods. Use balances.retrieve(customerId, { credit_entitlement_id }), not balances.get(creditId, customerId).
3. Using the wrong ledger argument order. createLedgerEntry receives customerId first; credit_entitlement_id belongs in the request object.
4. Using type or description for adjustments. Confirmed fields are entry_type and reason.
5. Getting the grants argument order wrong. creditEntitlements.balances.listGrants(customerID, params) does exist and takes the customer id first, with the entitlement supplied in the params object. It returns a paginated page, so read .items rather than treating the result as an array. Use customers.listCreditEntitlements(customerID) when you want the customer-level summary instead.
6. Treating available_balance as the balance API field. The confirmed balance response uses balance and overage; available_balance belongs to the dedicated low-balance webhook payload.
7. Choosing precision casually. It supports 0–10 for custom units and cannot be changed after creation.
8. Using JavaScript floating point for credits. API amounts are decimal strings. Preserve them as strings or use decimal arithmetic.
9. Exceeding adjustment bounds. Ledger amounts map to NUMERIC(38,28), and the integer part must be below 10^10.
10. Misstating monetary units. Currency amounts use the smallest currency unit. Do not label cents as dollars.
11. Using unstable idempotency keys. A timestamp or random key on every retry defeats deduplication. Derive the key from the immutable business operation.
12. Retrying an insufficient debit blindly. Manual debits can return 400 for insufficient balance; route the customer to top-up or your overage policy.
13. Assuming event ingestion is synchronous deduction. Meter-to-credit processing occurs approximately every minute.
14. Using Dodo's balance as a per-request lock. The docs explicitly warn against strict authorization from asynchronously reported meter balances.
15. Mismatching meter names. Usage event_name matching is case-sensitive.
16. Sending duplicate IDs within one batch. Duplicate event_id values in the same ingestion request reject the entire request. Previously ingested IDs are ignored on retry.
17. Inventing a deduplication window. Current docs require unique event IDs but do not publish a retention duration.
18. Getting conversion backward. meter_units_per_credit is usage units required for one credit, and is required when credit_entitlement_id is set.
19. Expecting a free threshold on credit-billed meters. free_threshold applies only to meters billed in money. When Bill usage in Credits is on, every unit deducts credits; model included usage as granted credits instead.
20. Supplying one rollover timeframe field. rollover_timeframe_count and rollover_timeframe_interval must be supplied together.
21. Using the wrong rollover enum case. Confirmed values are Day, Week, Month, and Year.
22. Assuming expiry happens before rollover. Rollover is applied first; only the remainder expires.
23. Inventing overage enum values. Use only forgive_at_reset, invoice_at_billing, carry_deficit, or carry_deficit_auto_repay.
24. Omitting overage pricing dependencies. Enabled overage requires price_per_unit; a price requires currency.
25. Attaching too many credits. The current product limit is five credit entitlements.
26. Assuming checkout grants arbitrary credits. Credits must already be attached to the purchased product or add-on.
27. Handling only the common webhooks. Include credit.overage_reset and credit.rollover_forfeited, not only added, deducted, and low-balance events.
28. Parsing an unverified webhook. Verify the raw body with client.webhooks.unwrap() as covered in webhook-integration; never hand-roll HMAC or trust re-serialized JSON.
29. Inventing historical snapshot APIs. Use ledger balance_before and balance_after for transaction-level history.
30. Using deprecated purchase methods. New checkout flows use client.checkoutSessions.create(...), not payments.create(...) or subscriptions.create(...).
31. Using the wrong host or key format. Valid hosts are https://test.dodopayments.com and https://live.dodopayments.com; keys start with dodo_test_ or dodo_live_.

Resources

• Credit-Based Billing Guide
• Create Credit Entitlement API
• Get Customer Balance API
• Create Ledger Entry API
• List Customer Ledger API
• Credit Webhook Reference
• Meter Guide
• Usage Event Ingestion API
• Create Product API