diff --git a/packages/wasm-utxo/js/coinName.ts b/packages/wasm-utxo/js/coinName.ts
index ed8e8ee..7dd350a 100644
--- a/packages/wasm-utxo/js/coinName.ts
+++ b/packages/wasm-utxo/js/coinName.ts
@@ -1,23 +1,66 @@
 // BitGo coin names (from Network::from_coin_name in src/networks.rs)
-export type CoinName =
-  | "btc"
-  | "tbtc"
-  | "tbtc4"
-  | "tbtcsig"
-  | "tbtcbgsig"
-  | "bch"
-  | "tbch"
-  | "bcha"
-  | "tbcha"
-  | "btg"
-  | "tbtg"
-  | "bsv"
-  | "tbsv"
-  | "dash"
-  | "tdash"
-  | "doge"
-  | "tdoge"
-  | "ltc"
-  | "tltc"
-  | "zec"
-  | "tzec";
+export const coinNames = [
+  "btc",
+  "tbtc",
+  "tbtc4",
+  "tbtcsig",
+  "tbtcbgsig",
+  "bch",
+  "tbch",
+  "bcha",
+  "tbcha",
+  "btg",
+  "tbtg",
+  "bsv",
+  "tbsv",
+  "dash",
+  "tdash",
+  "doge",
+  "tdoge",
+  "ltc",
+  "tltc",
+  "zec",
+  "tzec",
+] as const;
+
+export type CoinName = (typeof coinNames)[number];
+
+export function getMainnet(name: CoinName): CoinName {
+  switch (name) {
+    case "tbtc":
+    case "tbtc4":
+    case "tbtcsig":
+    case "tbtcbgsig":
+      return "btc";
+    case "tbch":
+      return "bch";
+    case "tbcha":
+      return "bcha";
+    case "tbtg":
+      return "btg";
+    case "tbsv":
+      return "bsv";
+    case "tdash":
+      return "dash";
+    case "tdoge":
+      return "doge";
+    case "tltc":
+      return "ltc";
+    case "tzec":
+      return "zec";
+    default:
+      return name;
+  }
+}
+
+export function isMainnet(name: CoinName): boolean {
+  return getMainnet(name) === name;
+}
+
+export function isTestnet(name: CoinName): boolean {
+  return getMainnet(name) !== name;
+}
+
+export function isCoinName(v: string): v is CoinName {
+  return (coinNames as readonly string[]).includes(v);
+}