diff --git a/ethers-core/src/types/chain.rs b/ethers-core/src/types/chain.rs
index 2acc6bf3..794c04aa 100644
--- a/ethers-core/src/types/chain.rs
+++ b/ethers-core/src/types/chain.rs
@@ -147,8 +147,8 @@ impl TryFrom<u64> for Chain {
             43113 => Chain::AvalancheFuji,
             11155111 => Chain::Sepolia,
             1284 => Chain::Moonbeam,
-            1281 => Chain::Moonbase,
-            1287 => Chain::MoonbeamDev,
+            1287 => Chain::Moonbase,
+            1281 => Chain::MoonbeamDev,
             1285 => Chain::Moonriver,
             10 => Chain::Optimism,
             69 => Chain::OptimismKovan,