How Billing Works
Every file you upload through Tusky involves two costs:| Cost Component | Token | Description |
|---|---|---|
| Walrus storage | WAL | Paid to Walrus storage nodes for blob storage across epochs. Rate determined by the Walrus network. |
| Gas fee | SUI | Sui network transaction fee for publishing the blob on-chain. |
Storage costs scale with file size and the number of storage epochs. Tusky passes through Walrus storage costs directly with no markup or infrastructure fee.
Funding Your Wallet
Open the wallet page
Navigate to Account → Wallet in the Tusky dashboard, or go directly to app.tusky.io/account/wallet.
Deposit SUI
Click Deposit SUI and approve the transfer from your connected Sui wallet. SUI is used for gas fees on Sui transactions.
Checking Your Balance
View your current SUI and WAL balances on the wallet page in the dashboard. The page shows:- Available balance — funds ready for storage operations
- Reserved balance — funds earmarked for in-progress uploads
- Estimated remaining storage — approximate storage capacity at current rates
Programmatic balance check
Use the SDK or API to check your balance programmatically:Low Balance Notifications
Tusky sends notifications when your wallet balance drops below the threshold needed for continued operations:- Warning — balance is running low, top up soon to avoid upload failures
- Critical — balance is insufficient for new uploads; existing stored files are unaffected
Pay-As-You-Go with x402
For applications that prefer per-request billing over prepaid balances, Tusky supports the x402 protocol — a standard for HTTP-native micropayments. With x402, each API request includes a payment header, and Tusky charges the exact cost of the operation in real time. This eliminates the need to maintain a prepaid balance.- How it works
- When to use x402
- Your application sends an API request to Tusky
- If the request requires payment, Tusky responds with a
402 Payment Requiredstatus and a payment specification - Your application signs a micropayment using your Sui wallet
- The request is retried with the payment proof in the header
- Tusky processes the request and settles the payment
Cost Estimation
Use the dashboard cost calculator or the upload cost API to preview costs before uploading. Pass a list of file sizes to get a per-file breakdown and totals:Cost estimates are based on current Walrus network rates and may fluctuate. The actual cost is determined at the time of the storage transaction.
Summary
| Feature | Prepaid Wallet | x402 Pay-As-You-Go |
|---|---|---|
| Funding model | Deposit SUI + WAL upfront | Pay per request via micropayment |
| Best for | High-volume, predictable usage | Sporadic, per-request billing |
| Overhead | Single deposit transaction | Payment header per request |
| Balance management | Manual top-ups with notifications | No balance to manage |