> ## Documentation Index > Fetch the complete documentation index at: https://docs.rails.wayex.com/llms.txt > Use this file to discover all available pages before exploring further. # Preview a stablecoin withdrawal > Calculates the effective withdrawal fee, total source debit, current eligibility, and any hold reason for a saved destination without creating an operation. ## What this endpoint does Calculates the effective withdrawal fee, total source debit, current eligibility, and any hold reason for a saved destination without creating an operation. ## When to use it Call it after the user chooses the active destination and amount, then show the returned terms on the final review screen before confirmation. ## Before you call Use a secret API key with `treasury:write`. The saved destination must belong to this tenant account and match an enabled asset and network. ## Money and balance effect Previewing does not reserve, debit, or send stablecoin. The create request rechecks the balance, destination, screening, limits, and provider capacity before reserving funds. ## States and completion `canProceed` reports current static eligibility. A `holdReason` identifies a current block or review path; only a later accepted create response records a durable reservation. ## Safe retries Send a unique `Idempotency-Key` for the logical action. If the response is lost, retry the same payload with the same key; never create a new key merely because the first response timed out. Read [Conversions and withdrawals](/treasury/conversions-and-withdrawals) for the complete workflow. ## OpenAPI ````yaml /api-reference/openapi.json post /v1/treasury/withdrawals/preview openapi: 3.0.0 info: title: Wayex API description: >- Wayex APIs for direct customer payment routes and isolated, prefunded Treasury accounts. Each API key is bound to one tenant account and its own wallet, settings, webhooks, and reporting. version: 1.0.0 contact: {} servers: - url: https://api.sandbox.wayex.com description: Sandbox integration environment security: - Bearer: [] - ApiKey: [] tags: - name: Treasury description: >- Prefunded AUD and stablecoin wallets for one isolated tenant account. Fund, pay, convert, withdraw, track, and reconcile without selecting another account. - name: Customers description: >- Onboard end customers, run verification, and manage each customer's entitlements. - name: Payment routes description: >- Standing deposit instructions per customer. When a customer funds a route, Wayex auto-converts at the live rate and pays out/sends — no quote, no lock. - name: Transfers description: >- Read the conversion records produced when customers fund payment routes — the live activity feed and per-conversion lifecycle timeline. - name: Rates description: >- The live indicative AUD↔stablecoin rate right now — the all-in rate Wayex quotes. Indicative only; the binding price is struck when a route's funds land. - name: Revenue description: Your developer-fee revenue over time. - name: Invoices description: >- Your monthly invoices — Wayex platform fees due, net of your accrued developer-fee credit. - name: Webhooks description: Subscribe to HMAC-signed event webhooks and inspect deliveries. - name: API keys description: Create, list, and rotate API keys for programmatic access. - name: Fees description: >- Configure your developer fee — the markup withheld from each conversion and credited against your monthly invoice. - name: Invitations description: Accept a team invitation and activate your account. paths: /v1/treasury/withdrawals/preview: post: tags: - Treasury summary: Preview a stablecoin withdrawal description: >- Calculates the effective withdrawal fee, total source debit, current eligibility, and any hold reason for a saved destination without creating an operation. Call it after the user chooses the active destination and amount, then show the returned terms on the final review screen before confirmation. operationId: TreasuryController2_previewWithdrawal_v1 parameters: - name: Idempotency-Key in: header required: true description: >- A unique key for this logical action. Reuse the same key and identical payload when retrying after an unknown response. schema: type: string minLength: 8 maxLength: 255 example: 13bda8d7-87bd-4fa4-b7d5-e740725f9bd2 requestBody: required: true content: application/json: schema: type: object properties: asset: type: string enum: - USDC - USDT network: type: string enum: - ethereum - base - arbitrum - optimism - polygon - bsc - avalanche - solana - tron amount: type: string pattern: ^\d+(\.\d+)?$ destinationId: type: string minLength: 1 externalReference: type: string minLength: 1 required: - asset - network - amount - externalReference - destinationId responses: '200': description: '' content: application/json: schema: type: object properties: principal: type: object properties: amount: type: string pattern: ^\d+(\.\d+)?$ currency: type: string enum: - AUD - USDC - USDT network: type: string enum: - ethereum - base - arbitrum - optimism - polygon - bsc - avalanche - solana - tron required: - amount - currency fee: type: object properties: amount: type: string pattern: ^\d+(\.\d+)?$ currency: type: string enum: - AUD - USDC - USDT network: type: string enum: - ethereum - base - arbitrum - optimism - polygon - bsc - avalanche - solana - tron required: - amount - currency sourceDebit: type: object properties: amount: type: string pattern: ^\d+(\.\d+)?$ currency: type: string enum: - AUD - USDC - USDT network: type: string enum: - ethereum - base - arbitrum - optimism - polygon - bsc - avalanche - solana - tron required: - amount - currency asset: type: string enum: - AUD - USDC - USDT network: type: string enum: - ethereum - base - arbitrum - optimism - polygon - bsc - avalanche - solana - tron configurationId: type: string minLength: 1 canProceed: type: boolean holdReason: type: string minLength: 1 required: - principal - fee - sourceDebit - asset - configurationId - canProceed security: - Bearer: [] - ApiKey: [] components: securitySchemes: Bearer: type: http scheme: bearer bearerFormat: Wayex API key description: 'Send the same Wayex API key as `Authorization: Bearer `.' ApiKey: type: apiKey in: header name: X-Api-Key description: A Wayex API key. Use a secret key for write operations. ````