> ## Documentation Index
> Fetch the complete documentation index at: https://docs.toju.network/llms.txt
> Use this file to discover all available pages before exploring further.

# Storage Payments

> How onchain payments work with SOL and USDFC

## Overview

We implement a pay-as-you-go model for decentralized storage using blockchain payments. Unlike traditional cloud storage with monthly subscriptions, users pay only for what they store and for how long. We currently support **SOL** (Solana) and **USDFC** (Filecoin).

## How It Works

<Steps>
  <Step title="Select Files">
    Choose one or more files to upload to decentralized storage
  </Step>

  <Step title="Choose Duration">
    Specify how long you want to store the files (minimum 7 days)
  </Step>

  <Step title="Get Cost Estimate">
    The system calculates the cost based on:

    * Total file size
    * Storage duration
    * Current network rates
  </Step>

  <Step title="Sign Transaction">
    Approve the payment with your wallet (Phantom for SOL, MetaMask for USDFC)
  </Step>

  <Step title="Onchain Deposit">
    For SOL: a deposit is created on the Solana blockchain via our smart contract. For USDFC: a token transfer is sent on Filecoin.
  </Step>

  <Step title="Storage Provisioned">
    We pin your files to IPFS. The CID is linked to your payment and stored in our database.
  </Step>
</Steps>

## Cost Calculation

Storage costs are calculated using this formula:

```
Cost (SOL) = (File Size in MB × Duration in Days × Base Rate) + Transaction Fee
```

The base rate is dynamically calculated to cover IPFS storage costs while keeping prices competitive.

<Info>
  You can estimate costs before uploading using the `estimateStorageCost` SDK method.
</Info>

## Payment Flow

```mermaid theme={null}
sequenceDiagram
    participant User
    participant Wallet
    participant Server
    participant IPFS
    participant Contract

    User->>Server: Upload files + request deposit instructions
    Server->>IPFS: Pin files
    IPFS-->>Server: Return CID
    Server-->>User: Return CID + payment instructions
    User->>Wallet: Sign transaction
    Wallet->>Contract: Send payment (SOL deposit or USDFC transfer)
    User->>Server: Submit transaction signature
    Server->>Contract: Verify payment onchain
    Server-->>User: Confirm upload with CID + URL
```

## Payment Model

When you pay for storage:

1. **Files are pinned** to IPFS before the deposit is created
2. **Payment is processed** — SOL via our smart contract, or USDFC via direct token transfer
3. **Files are accessible** for the full duration you paid for

Your payment covers the cost of storing your data on IPFS through our infrastructure. The smart contract (SOL) provides on-chain accounting and deposit verification, while USDFC payments are direct token transfers.

This model ensures:

* No recurring subscriptions or credit cards needed
* Transparent, verifiable payments on-chain
* Storage guaranteed for the full paid duration
* Simple one-time payment per upload

## Transaction Records

Every payment is recorded both:

<CardGroup cols={2}>
  <Card title="Onchain" icon="link">
    Permanent record on Solana blockchain with transaction signature
  </Card>

  <Card title="Database" icon="database">
    Indexed in our database for quick lookup and history tracking
  </Card>
</CardGroup>

## Supported Payment Chains

We currently support two payment methods:

* **SOL (Solana)**: Payments via our Solana smart contract with on-chain deposit verification
* **USDFC (Filecoin)**: Direct stablecoin transfers on Filecoin (1:1 with USD)

Coming soon:

* **Base (ETH)**: Ethereum L2 payments for lower gas fees
* **Additional chains**: Based on community demand

<Note>
  All payment methods store data on the same IPFS network. You choose whichever chain you prefer — the storage experience is identical.
</Note>

## Benefits

**For Users:**

* No credit card required
* Pay only for what you use
* Transparent, verifiable costs
* No recurring subscriptions

**For Developers:**

* Easy integration with crypto wallets
* No payment processing fees
* Instant settlement
* Global accessibility

## Limitations

<Warning>
  **No refunds**: Once files are uploaded, storage is provisioned and payments cannot be refunded. Make sure you've selected the correct duration before confirming.
</Warning>

* Minimum storage duration: 7 days
* Gas fees apply for each transaction
* Requires sufficient wallet balance
* Files expire after storage duration ends