diff --git a/contracts/sumtree-orderbook/src/contract.rs b/contracts/sumtree-orderbook/src/contract.rs
index aec8330..5bd93bb 100644
--- a/contracts/sumtree-orderbook/src/contract.rs
+++ b/contracts/sumtree-orderbook/src/contract.rs
@@ -122,6 +122,16 @@ pub fn query(deps: Deps, _env: Env, msg: QueryMsg) -> ContractResult<Binary> {
             token_out_denom,
             swap_fee,
         )?)?),
+        QueryMsg::CalcOutAmtGivenIn {
+            token_in,
+            token_out_denom,
+            swap_fee,
+        } => Ok(to_json_binary(&query::calc_out_amount_given_in(
+            deps,
+            token_in,
+            token_out_denom,
+            swap_fee,
+        )?)?),
         QueryMsg::GetTotalPoolLiquidity {} => {
             Ok(to_json_binary(&query::total_pool_liquidity(deps)?)?)
         }
diff --git a/contracts/sumtree-orderbook/src/msg.rs b/contracts/sumtree-orderbook/src/msg.rs
index 058fdff..b9d1c9b 100644
--- a/contracts/sumtree-orderbook/src/msg.rs
+++ b/contracts/sumtree-orderbook/src/msg.rs
@@ -79,6 +79,13 @@ pub enum QueryMsg {
         token_out_denom: String,
         swap_fee: Decimal,
     },
+    // Duplicate of the above, but for compatibility CosmWasm Pool module
+    #[returns(CalcOutAmtGivenInResponse)]
+    CalcOutAmtGivenIn {
+        token_in: Coin,
+        token_out_denom: String,
+        swap_fee: Decimal,
+    },
     #[returns(GetTotalPoolLiquidityResponse)]
     GetTotalPoolLiquidity {},
     /// NO-OP QUERY