diff --git a/substrate/primitives/weights/Cargo.toml b/substrate/primitives/weights/Cargo.toml
index 163b241276cec..fb2e2ae8cb1a0 100644
--- a/substrate/primitives/weights/Cargo.toml
+++ b/substrate/primitives/weights/Cargo.toml
@@ -21,6 +21,7 @@ smallvec = "1.11.0"
 sp-arithmetic = { path = "../arithmetic", default-features = false }
 sp-debug-derive = { path = "../debug-derive", default-features = false }
 sp-std = { path = "../std", default-features = false }
+schemars = { version = "0.8.3", default-features = false, optional = true }
 
 [features]
 default = ["std"]
@@ -44,3 +45,7 @@ serde = [
 	"scale-info/serde",
 	"sp-arithmetic/serde",
 ]
+
+json-schema = [
+	"dep:schemars",
+]
diff --git a/substrate/primitives/weights/src/weight_v2.rs b/substrate/primitives/weights/src/weight_v2.rs
index d692aaff8f5ab..3c10929f433b6 100644
--- a/substrate/primitives/weights/src/weight_v2.rs
+++ b/substrate/primitives/weights/src/weight_v2.rs
@@ -23,6 +23,7 @@ use super::*;
 
 #[derive(Encode, Decode, MaxEncodedLen, TypeInfo, Eq, PartialEq, Copy, Clone, Debug, Default)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "json-schema", derive(schemars::JsonSchema))]
 pub struct Weight {
 	#[codec(compact)]
 	/// The weight of computational time used based on some reference hardware.