> ## Documentation Index > Fetch the complete documentation index at: https://documentation.nozle.dev/llms.txt > Use this file to discover all available pages before exploring further. # Estimate instant fees for a pay in advance charge > Estimate the fees that would be created after reception of an event for a billable metric attached to one or multiple pay in advance standard or percentage charges ## OpenAPI ````yaml /lago-openapi.yaml post /events/estimate_instant_fees openapi: 3.1.0 info: title: Nozle Billing API description: >- Nozle Billing API allows your application to push customer information and metrics (events) from your application to the billing engine. version: 1.49.0 license: name: AGPLv3 url: https://github.com/getlago/lago-openapi/blob/main/LICENSE contact: email: tech@getlago.com servers: - url: https://core.nozle.app/api/v1 description: Nozle Billing API security: - bearerAuth: [] tags: - name: Activity Logs description: Everything about Activity logs externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/audit-logs/activity-logs-object - name: Analytics description: Everything about Analytics - name: API Logs description: Everything about API logs externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/audit-logs/api-logs-object - name: Billable Metrics description: Everything about Billable metric collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/billable-metrics/object - name: Features description: Everything about Feature collection externalDocs: description: Find out more url: >- https://getlago.com/docs/api-reference/entitlements/features/feature-object - name: Entitlements description: Everything about Entitlement collection externalDocs: description: Find out more url: >- https://getlago.com/docs/api-reference/entitlements/plan-entitlements/plan-entitlement-object - name: Billing Entities description: Everything about Billing Entities externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/billing-entities/object - name: Customers description: Everything about Customer collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/customers/object - name: Plans description: Everything about Plan collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/plans/object - name: Subscriptions description: Everything about Subscription collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/subscriptions/subscription-object - name: Events description: Everything about Event collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/events/event-object - name: Organizations description: Everything about Organization collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/organizations/organization-object - name: Taxes description: Everything about Tax collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/taxes/tax-object - name: Coupons description: Everything about Coupon collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/coupons/coupon-object - name: Add-ons description: Everything about Add-on collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/add-ons/add-on-object - name: Fees description: Everything about Fees externalDocs: description: Find out more url: >- https://getlago.com/docs/api-reference/invoices/invoice-object#fee-object - name: Invoices description: Everything about Invoice collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/invoices/invoice-object - name: Wallets description: Everything about Wallet collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/wallets/wallet-object - name: Credit Notes description: Everything about Credit notes collection externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/credit-notes/credit-note-object - name: Webhooks description: Everything about Webhooks externalDocs: description: Find out more url: >- https://getlago.com/docs/api-reference/webhooks/format---signature#1-retrieve-the-public-key - name: Webhook Endpoints description: Everything about Webhook Endpoints externalDocs: description: Find out more url: >- https://getlago.com/docs/api-reference/webhook-endpoints/webhook-endpoint-object - name: Payment Receipts description: Everything about Payment receipts externalDocs: description: Find out more url: >- https://getlago.com/docs/api-reference/payment-receipts/payment-receipt-object - name: Payment Requests description: Everything about PaymentRequests externalDocs: description: Find out more url: >- https://getlago.com/docs/api-reference/payment-requests/payment-request-object - name: Payments description: Everything about Payments externalDocs: description: Find out more url: https://getlago.com/docs/api-reference/payments/payment-object - name: Payment Methods description: Everything about Payment Methods externalDocs: description: Find out more url: >- https://getlago.com/docs/api-reference/payment-methods/payment-method-object externalDocs: description: Lago Github url: https://github.com/getlago paths: /events/estimate_instant_fees: post: tags: - Events summary: Estimate instant fees for a pay in advance charge description: >- Estimate the fees that would be created after reception of an event for a billable metric attached to one or multiple pay in advance standard or percentage charges operationId: eventEstimateInstantFees requestBody: description: Event estimate instant payload content: application/json: schema: $ref: '#/components/schemas/EventEstimateInstantFeesInput' required: true responses: '200': description: Fees estimate content: application/json: schema: $ref: '#/components/schemas/FeesEstimate' '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '404': $ref: '#/components/responses/NotFound' '422': $ref: '#/components/responses/UnprocessableEntity' components: schemas: EventEstimateInstantFeesInput: type: object required: - event properties: event: type: object required: - code - external_subscription_id properties: code: type: string example: storage description: >- The code that identifies a targeted billable metric. It is essential that this code matches the `code` property of one of your active billable metrics. If the provided code does not correspond to any active billable metric, it will be ignored during the process. external_subscription_id: type: string example: sub_1234567890 description: >- The unique identifier of the subscription within your application. properties: type: object description: >- This field represents additional properties associated with the event, which are utilized in the calculation of the final fee. This object becomes mandatory when the targeted billable metric employs a `sum_agg`, `max_agg`, or `unique_count_agg` aggregation method. However, when using a simple `count_agg`, this object is not required. transaction_id: type: - string - 'null' example: transaction_1234567890 description: This field represents a unique identifier for the event. FeesEstimate: type: object required: - Fees properties: fees: type: array items: $ref: '#/components/schemas/FeeEstimateObject' FeeEstimateObject: type: object required: - item - amount_cents - amount_currency - taxes_amount_cents - taxes_rate - total_amount_cents - total_amount_currency - pay_in_advance - invoiceable - units - precise_unit_amount - payment_status properties: lago_id: type: 'null' lago_charge_id: type: string format: uuid description: Unique identifier assigned to the charge that the fee belongs to example: 1a901a90-1a90-1a90-1a90-1a901a901a90 lago_charge_filter_id: type: - string - 'null' format: uuid description: >- Unique identifier assigned to the charge filter that the fee belongs to example: 1a901a90-1a90-1a90-1a90-1a901a901a90 lago_invoice_id: type: 'null' lago_true_up_fee_id: type: 'null' lago_true_up_parent_fee_id: type: 'null' lago_subscription_id: type: string format: uuid description: >- Unique identifier assigned to the subscription, created by Lago. This field is specifically displayed when the fee type is charge or subscription. example: 1a901a90-1a90-1a90-1a90-1a901a901a90 lago_customer_id: type: string format: uuid description: >- Unique identifier assigned to the customer, created by Lago. This field is specifically displayed when the fee type is charge or subscription. example: 1a901a90-1a90-1a90-1a90-1a901a901a90 external_customer_id: type: string description: >- Unique identifier assigned to the customer in your application. This field is specifically displayed when the fee type is charge or subscription. example: external_id external_subscription_id: type: string description: >- Unique identifier assigned to the subscription in your application. This field is specifically displayed when the fee type is charge or subscription. example: external_id amount_cents: type: integer description: The cost of this specific fee, excluding any applicable taxes. example: 100 precise_amount: type: number description: >- The cost of this specific fee, excluding any applicable taxes, with precision. example: 1.0001 precise_total_amount: type: number description: >- The cost of this specific fee, including any applicable taxes, with precision. example: 1.0212 amount_currency: $ref: '#/components/schemas/Currency' description: >- The currency of this specific fee. It indicates the monetary unit in which the fee's cost is expressed. example: EUR taxes_amount_cents: type: integer description: The cost of the tax associated with this specific fee. example: 0 taxes_precise_amount: type: number description: >- The cost of the tax associated with this specific fee, with precision. example: 0 taxes_rate: type: number description: The tax rate associated with this specific fee. example: 20 units: type: string description: >- The number of units used to charge the customer. This field indicates the quantity or count of units consumed or utilized in the context of the charge. It helps in determining the basis for calculating the fee or cost associated with the usage of the service or product provided to the customer. example: '0.32' description: type: 'null' precise_unit_amount: type: number description: The unit amount of the fee per unit, with precision. example: 312.5 precise_coupons_amount_cents: type: string description: >- The coupon amount applied to the estimated instant fee. It will always returns 0 example: '0.0' total_amount_cents: type: integer description: The cost of this specific fee, including any applicable taxes. example: 120 total_amount_currency: $ref: '#/components/schemas/Currency' description: The currency of this specific fee, including any applicable taxes. example: EUR events_count: type: integer description: >- The number of events that have been sent and used to charge the customer. This field indicates the count or quantity of events that have been processed and considered in the charging process. example: 1 pay_in_advance: type: boolean description: >- Flag that indicates whether the fee was paid in advance. It serves as a boolean value, where `true` represents that the fee was paid in advance (straightaway), and `false` indicates that the fee was not paid in arrears (at the end of the period). example: true invoiceable: type: boolean description: >- Flag that indicates whether the fee was included on the invoice. It serves as a boolean value, where `true` represents that the fee was included on the invoice, and `false` indicates that the fee was not included on the invoice. example: true payment_status: type: string enum: - pending description: >- Indicates the payment status of the fee. It represents the current status of the payment associated with the fee. The value will always `pending`. example: pending created_at: type: 'null' succeeded_at: type: 'null' failed_at: type: 'null' refunded_at: type: 'null' event_transaction_id: type: string description: >- Unique identifier assigned to the transaction. This field is specifically displayed when the fee type is `charge` and the payment for the fee is made in advance (`pay_in_advance` is set to `true`). example: transaction_1234567890 amount_details: type: 'null' item: type: object description: Item attached to the fee required: - type - code - name - lago_item_id - item_type properties: type: type: string enum: - charge description: The fee type. The value will be `charge`. example: charge code: type: string description: >- The code of the fee item. It will be the code of the `billable_metric`. example: startup name: type: string description: >- The name of the fee item. It will be the name of the `billable_metric`. example: Startup description: type: string description: >- The description of the fee item. It will be the name of the `billable_metric`. example: Startup description invoice_display_name: type: string description: >- Specifies the name that will be displayed on an invoice. If no value is set for this field, the name of the actual charge will be used as the default display name. example: Setup Fee (SF1) filter_invoice_display_name: type: - string - 'null' description: >- Specifies the name that will be displayed on an invoice. If no value is set for this field, the actual charge filter values will be used as the default display name. example: AWS eu-east-1 filters: type: - object - 'null' description: Key value list of event properties additionalProperties: type: array items: type: string lago_item_id: type: string example: 1a901a90-1a90-1a90-1a90-1a901a901a90 description: >- Unique identifier of the fee item, created by Lago. It will be the identifier of the `billable_metric`. format: uuid item_type: type: string enum: - BillableMetric description: The type of the fee item. Values is `BillableMetric`. example: BillableMetric grouped_by: type: object description: >- Key value list of event properties aggregated by the charge model additionalProperties: type: string ApiErrorBadRequest: type: object required: - status - error properties: status: type: integer format: int32 example: 400 error: type: string example: Bad request ApiErrorUnauthorized: type: object required: - status - error properties: status: type: integer format: int32 example: 401 error: type: string example: Unauthorized ApiErrorForbidden: type: object required: - status - error - code properties: status: type: integer format: int32 example: 403 error: type: string example: Forbidden code: type: string example: feature_unavailable ApiErrorNotFound: type: object required: - status - error - code properties: status: type: integer format: int32 example: 404 error: type: string example: Not Found code: type: string example: object_not_found ApiErrorUnprocessableEntity: type: object required: - status - error - code - error_details properties: status: type: integer format: int32 example: 422 error: type: string example: Unprocessable entity code: type: string example: validation_errors error_details: type: object Currency: type: string example: USD enum: - AED - AFN - ALL - AMD - ANG - AOA - ARS - AUD - AWG - AZN - BAM - BBD - BDT - BGN - BIF - BMD - BND - BOB - BRL - BSD - BWP - BYN - BZD - CAD - CDF - CHF - CLF - CLP - CNY - COP - CRC - CVE - CZK - DJF - DKK - DOP - DZD - EGP - ETB - EUR - FJD - FKP - GBP - GEL - GHS - GIP - GMD - GNF - GTQ - GYD - HKD - HNL - HRK - HTG - HUF - IDR - ILS - INR - ISK - JMD - JPY - KES - KGS - KHR - KMF - KRW - KYD - KZT - LAK - LBP - LKR - LRD - LSL - MAD - MDL - MGA - MKD - MMK - MNT - MOP - MRO - MUR - MVR - MWK - MXN - MYR - MZN - NAD - NGN - NIO - NOK - NPR - NZD - PAB - PEN - PGK - PHP - PKR - PLN - PYG - QAR - RON - RSD - RUB - RWF - SAR - SBD - SCR - SEK - SGD - SHP - SLL - SOS - SRD - STD - SZL - THB - TJS - TOP - TRY - TTD - TWD - TZS - UAH - UGX - USD - UYU - UZS - VND - VUV - WST - XAF - XCD - XOF - XPF - YER - ZAR - ZMW responses: BadRequest: description: Bad Request error content: application/json: schema: $ref: '#/components/schemas/ApiErrorBadRequest' Unauthorized: description: Unauthorized error content: application/json: schema: $ref: '#/components/schemas/ApiErrorUnauthorized' Forbidden: description: Forbidden content: application/json: schema: $ref: '#/components/schemas/ApiErrorForbidden' NotFound: description: Not Found error content: application/json: schema: $ref: '#/components/schemas/ApiErrorNotFound' UnprocessableEntity: description: Unprocessable entity error content: application/json: schema: $ref: '#/components/schemas/ApiErrorUnprocessableEntity' securitySchemes: bearerAuth: type: http scheme: bearer ````