diff --git a/packages/crypto/src/index.ts b/packages/crypto/src/index.ts
index 3eccee6d..b39e4986 100644
--- a/packages/crypto/src/index.ts
+++ b/packages/crypto/src/index.ts
@@ -9,6 +9,7 @@ export {
   Xchacha20poly1305IetfKey,
   Xchacha20poly1305IetfMessage,
   Xchacha20poly1305IetfNonce,
+  xchacha20NonceLength,
   Argon2id,
   Argon2idOptions,
   Ed25519,
diff --git a/packages/crypto/src/libsodium.ts b/packages/crypto/src/libsodium.ts
index a094a8e5..a27b0c9d 100644
--- a/packages/crypto/src/libsodium.ts
+++ b/packages/crypto/src/libsodium.ts
@@ -91,6 +91,13 @@ export class Ed25519 {
   }
 }
 
+/**
+ * Nonce length in bytes for all flavours of XChaCha20.
+ *
+ * @see https://libsodium.gitbook.io/doc/advanced/stream_ciphers/xchacha20#notes
+ */
+export const xchacha20NonceLength = 24;
+
 export class Xchacha20poly1305Ietf {
   public static async encrypt(
     message: Xchacha20poly1305IetfMessage,
diff --git a/packages/crypto/types/index.d.ts b/packages/crypto/types/index.d.ts
index 3eccee6d..b39e4986 100644
--- a/packages/crypto/types/index.d.ts
+++ b/packages/crypto/types/index.d.ts
@@ -9,6 +9,7 @@ export {
   Xchacha20poly1305IetfKey,
   Xchacha20poly1305IetfMessage,
   Xchacha20poly1305IetfNonce,
+  xchacha20NonceLength,
   Argon2id,
   Argon2idOptions,
   Ed25519,
diff --git a/packages/crypto/types/libsodium.d.ts b/packages/crypto/types/libsodium.d.ts
index d045971f..1ab48dca 100644
--- a/packages/crypto/types/libsodium.d.ts
+++ b/packages/crypto/types/libsodium.d.ts
@@ -31,6 +31,12 @@ export declare class Ed25519 {
   static createSignature(message: Uint8Array, keyPair: Ed25519Keypair): Promise<Uint8Array>;
   static verifySignature(signature: Uint8Array, message: Uint8Array, pubkey: Uint8Array): Promise<boolean>;
 }
+/**
+ * Nonce length in bytes for all flavours of XChaCha20.
+ *
+ * @see https://libsodium.gitbook.io/doc/advanced/stream_ciphers/xchacha20#notes
+ */
+export declare const xchacha20NonceLength = 24;
 export declare class Xchacha20poly1305Ietf {
   static encrypt(
     message: Xchacha20poly1305IetfMessage,