The problem
One flat slippage value can’t fit every token. Set it tight and volatile tokens revert, so the user pays gas for a failed swap. Set it loose and stable tokens give away value that a tighter bound would have kept. A single number can’t be right for both.How LI.FI solves it
LI.FI resolves a recommended slippage for the tokens a route touches and either applies it as the server-side default for the quote, or surfaces it to you as an advisory value so your client can decide. When a route crosses more than one token, LI.FI takes the highest recommended slippage among those tokens, so the most volatile token in the path doesn’t cause a revert. A slippage value you pass yourself is always respected and takes precedence over the recommendation.What you see as an integrator
When Smart Slippage is enabled for your integrator key, each step in the route response carries arecommendedSlippage field. Read it per step and apply it in your client, or let LI.FI apply it as the default when you don’t set your own.
The field has three states, and the distinction matters:
- A number. A recommendation resolved for that step, expressed as a decimal fraction. For example,
0.005means 0.5 percent. null. The feature is active for your integrator, but no recommendation resolved for that step. This lets you tell “no data for this token” apart from “feature not enabled.”- Field absent. The feature isn’t enabled for your integrator, so no recommendation was produced.
Your own slippage always wins. If you pass a slippage value on the request, LI.FI uses it and doesn’t override it with a recommendation.
Scope
- Enabled per integrator. When it’s off, the
recommendedSlippagefield is absent and quote behavior is unchanged. - Applies to both same-chain and cross-chain routes.
- Recommendations reflect current market data. Where LI.FI has no current data for a token, the value resolves to
nullfor that step rather than falling back to a guess.
Availability
Smart Slippage is an enterprise feature, enabled per integrator.Contact the LI.FI team to enable
Tell us which tokens and chains you route most. We confirm coverage and enable Smart Slippage for your integrator key.

