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The /quote endpoint is the starting point for every trade on CoW Protocol. Before a user can sign an intent, the protocol needs to determine what price is available and what fees apply. This page explains how quoting works, the different quoting strategies available, and best practices for keeping quotes fresh.

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How Quoting Works

When you call POST /api/v1/quote, the protocol:
  1. Evaluates available liquidity across on-chain sources (AMMs, aggregators) and off-chain sources (CoW Protocol solvers)
  2. Estimates network costs (gas) for settlement
  3. Returns a price estimate including fee breakdowns
curl -X POST "https://api.cow.fi/mainnet/api/v1/quote" \
  -H "Content-Type: application/json" \
  -d '{
    "sellToken": "0xA0b86a33E6411Ec5d0b9dd2E7dC15A9CAA6C1F8e",
    "buyToken": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
    "sellAmountBeforeFee": "1000000000000000000",
    "kind": "sell",
    "from": "0xYourWalletAddress"
  }'
Quotes are not guaranteed. They represent the best estimate at the time of the request. Market conditions, gas prices, and available liquidity can all change between when a quote is fetched and when the order is executed.
Every quote response includes a validTo timestamp. The signed order must be submitted before this time expires, or it will be rejected.

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Quote Types

CoW Protocol supports different quoting strategies via the priceQuality parameter, allowing you to trade off between response speed and price accuracy.

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Fast Quotes

curl -X POST "https://api.cow.fi/mainnet/api/v1/quote" \
  -H "Content-Type: application/json" \
  -d '{
    "sellToken": "0xA0b86a33E6411Ec5d0b9dd2E7dC15A9CAA6C1F8e",
    "buyToken": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
    "sellAmountBeforeFee": "1000000000000000000",
    "kind": "sell",
    "from": "0xYourWalletAddress",
    "priceQuality": "fast"
  }'
  • Returns quickly (typically under 1 second)
  • Uses cached or approximate pricing data
  • Best for UI display, price previews, and showing users an estimate before they commit
  • Trade-off: price may be less accurate, especially for large orders or illiquid token pairs

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Optimal Quotes

curl -X POST "https://api.cow.fi/mainnet/api/v1/quote" \
  -H "Content-Type: application/json" \
  -d '{
    "sellToken": "0xA0b86a33E6411Ec5d0b9dd2E7dC15A9CAA6C1F8e",
    "buyToken": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
    "sellAmountBeforeFee": "1000000000000000000",
    "kind": "sell",
    "from": "0xYourWalletAddress",
    "priceQuality": "optimal"
  }'
  • This is the default when priceQuality is not specified
  • Takes longer (typically 1-5 seconds)
  • Queries multiple liquidity sources and solvers for the best available price
  • Best for order signing and final price confirmation in production order flows
  • Trade-off: slower response time

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Verified Quotes

curl -X POST "https://api.cow.fi/mainnet/api/v1/quote" \
  -H "Content-Type: application/json" \
  -d '{
    "sellToken": "0xA0b86a33E6411Ec5d0b9dd2E7dC15A9CAA6C1F8e",
    "buyToken": "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2",
    "sellAmountBeforeFee": "50000000000000000000000",
    "kind": "sell",
    "from": "0xYourWalletAddress",
    "priceQuality": "verified"
  }'
  • Most thorough price discovery process
  • Verifies that the proposed settlement is feasible on-chain
  • Best for large orders where accuracy is critical
  • Trade-off: longest response time (3-10 seconds)

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Comparison

PropertyFastOptimalVerified
Response timeUnder 1s1–5s3–10s
Price accuracyApproximateGoodBest
Use caseUI previewOrder signingLarge/critical orders
Recommended forPrice displayMost integrationsDAOs, large trades

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Timing Between Quote and Order

The time gap between fetching a quote and submitting the signed order is one of the most common sources of integration bugs.
A quote is a snapshot of market conditions. The longer you wait between receiving a quote and submitting the signed order, the more likely it is that market conditions have changed and the order will not fill.

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The validTo field

Every quote response includes a validTo timestamp (Unix epoch seconds). This defines the latest point at which the order can still be considered valid by the protocol. If you submit an order after validTo has passed, it will be rejected.
1

Fetch a quote

Call /api/v1/quote with the user’s trade parameters.
2

Display to user

Show the estimated amounts, fees, and exchange rate in your UI.
3

User confirms

Wait for the user to review and click “Confirm” or “Swap”.
4

Re-quote if stale

If more than 30 seconds have elapsed since the quote was fetched, fetch a new quote before proceeding.
5

Sign with quote amounts

Build the order using the quote’s sellAmount, buyAmount, and feeAmount values, apply slippage, and have the user sign it.
6

Submit immediately

Send the signed order to POST /api/v1/orders right away. Do not hold it.

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Anti-patterns to avoid

  • Caching quotes for minutes. A quote fetched 5 minutes ago is almost certainly stale. Prices, gas costs, and liquidity can all shift in that time.
  • Quoting once on page load. If your UI fetches a quote when the page loads and uses it when the user clicks “Swap” minutes later, the order is unlikely to fill at the quoted price.
  • Ignoring validTo. Even if you submit before validTo, a very old quote means the signed amounts may not match current market conditions, leading to unfilled orders.

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Slippage and Quote Freshness

Slippage tolerance and quote freshness are closely related. Slippage defines how much worse than the quoted price a user is willing to accept:
  • Tight slippage + stale quote = high chance the order expires without filling, because the market has already moved beyond the narrow tolerance window.
  • Wide slippage + stale quote = order may fill, but the user could receive a significantly worse price than expected.
  • Fresh quote + reasonable slippage = the ideal combination. The quoted price is close to the current market, and the slippage buffer handles normal short-term volatility.
As a general rule, re-quote if more than 30 seconds have elapsed since the last quote. For volatile markets or large orders, consider re-quoting even more frequently.

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Best Practices for Integrators

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For frontend/UI integrations

  • Use priceQuality: "fast" for initial price previews and display
  • Switch to priceQuality: "optimal" when the user is ready to sign
  • Implement a quote refresh mechanism: periodically re-fetch the quote while the user is on the confirmation screen
  • Show a visual indicator when the quote is being refreshed so users understand why amounts may change

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For bots and automated systems

  • Always use fresh quotes immediately before signing — never cache
  • Use priceQuality: "optimal" as the baseline
  • For large orders, use priceQuality: "verified" or consider splitting into a TWAP order to reduce market impact

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For large or DAO trades

  • Use priceQuality: "verified" to confirm settlement feasibility before signing
  • Consider TWAP orders to spread execution over time and reduce slippage
  • Set slippage tolerance carefully — too tight and the order will not fill; too loose and you may lose value

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General guidelines

// Example: quote refresh logic
async function getQuoteWithRefresh(params: QuoteParams): Promise<QuoteResponse> {
  const quote = await fetchQuote(params);
  const quoteTimestamp = Date.now();

  // Before signing, check if the quote is still fresh
  function isQuoteFresh(): boolean {
    return Date.now() - quoteTimestamp < 30_000; // 30 seconds
  }

  // If the user takes too long, re-fetch
  if (!isQuoteFresh()) {
    return fetchQuote(params);
  }

  return quote;
}
Never use --no-verify or skip quote validation in production. Always confirm that the quote’s validTo has not passed before submitting the signed order.

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Further Reading

Last modified on March 12, 2026