Quote

The quote endpoint returns a projected conversion result for a given source token, destination token, and amount. Use it to show fee breakdowns and expected output to users before they initiate a deposit or withdrawal.

Endpoint

POST https://bridge.openfish.fun/quote

Request Body

Field	Type	Required	Description
from_chain_id	string	Yes	Source chain ID (e.g., "1" for Ethereum)
from_token_address	string	Yes	Token contract address on the source chain
to_token_address	string	Yes	Token contract address on the destination chain
from_amount_base_unit	string	Yes	Amount to convert in base units (e.g., "10000000" for 10 USDC)

Example Request

curl -X POST https://bridge.openfish.fun/quote \
  -H "Content-Type: application/json" \
  -d '{
    "from_chain_id": "1",
    "from_token_address": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
    "to_token_address": "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174",
    "from_amount_base_unit": "10000000"
  }'

Response

{
  "estimated_output": "9985000",
  "estimated_output_usd": 9.985,
  "gas_cost_usd": 0.012,
  "bridge_fee_usd": 0.003,
  "slippage_percent": 0.05,
  "route": "1inch",
  "expires_at": 1700000000
}

Response Fields

Field	Type	Description
estimated_output	string	Expected output amount in destination base units
estimated_output_usd	number	Estimated output value in USD
gas_cost_usd	number	Estimated gas fee in USD
bridge_fee_usd	number	Bridge routing fee in USD
slippage_percent	number	Estimated price slippage as a percentage
route	string	Aggregator used for the swap route
expires_at	number	Unix timestamp when the quote expires

Rust SDK Example

use openfish_client_sdk::BridgeClient;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let bridge = BridgeClient::new("https://bridge.openfish.fun");

    let quote = bridge
        .quote(
            "1",                                                    // Ethereum
            "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",          // USDC on Ethereum
            "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174",          // USDC.e on Polygon
            "10000000",                                             // 10 USDC
        )
        .await?;

    println!("Estimated output: {} base units", quote.estimated_output);
    println!("Gas cost: ${:.4}", quote.gas_cost_usd);
    println!("Slippage: {:.2}%", quote.slippage_percent);

    Ok(())
}

How It Works

Openfish routes quote calculations through the 1inch aggregator API, finding the best swap path between source and destination tokens. The returned estimate factors in:

• Gas costs on both the source and destination chains.
• Bridge fees imposed by the underlying cross-chain relay.
• Swap slippage determined by current DEX pool depth.

Quotes are informational projections. The actual output may shift slightly due to price movement between quote time and execution.

When to Use Quotes

• Before a deposit, to preview the USDC.e amount that will be credited.
• Before a withdrawal, to show the expected destination token amount.
• To compare costs across different source tokens or source chains.

Quote Expiry

Every quote carries an expires_at timestamp. Once expired, the estimate is stale and should be refreshed. Quotes are typically valid for 30 seconds.

Next Steps

• Deposit — Execute a deposit after reviewing the quote.
• Withdraw — Execute a withdrawal after reviewing the quote.
• Supported Assets — Check which tokens and chains are available.