diff --git a/_data/chains/eip155-204.json b/_data/chains/eip155-204.json
new file mode 100644
index 000000000000..2e350bb2140d
--- /dev/null
+++ b/_data/chains/eip155-204.json
@@ -0,0 +1,23 @@
+{
+  "name": "opBNB Mainnet",
+  "chain": "opBNB",
+  "rpc": ["https://opbnb-mainnet-rpc.bnbchain.org"],
+  "faucets": ["https://free-online-app.com/faucet-for-eth-evm-chains"],
+  "nativeCurrency": {
+    "name": "BNB Chain Native Token",
+    "symbol": "BNB",
+    "decimals": 18
+  },
+  "infoURL": "https://opbnb.bnbchain.org/en",
+  "shortName": "obnb",
+  "chainId": 204,
+  "networkId": 204,
+  "slip44": 714,
+  "explorers": [
+    {
+      "name": "opbnbscan",
+      "url": "http://mainnet.opbnbscan.com",
+      "standard": "EIP3091"
+    }
+  ]
+}
diff --git a/_data/chains/eip155-5611.json b/_data/chains/eip155-5611.json
new file mode 100644
index 000000000000..e95ed0aa585d
--- /dev/null
+++ b/_data/chains/eip155-5611.json
@@ -0,0 +1,27 @@
+{
+  "name": "opBNB Testnet",
+  "chain": "opBNB",
+  "rpc": ["https://opbnb-testnet-rpc.bnbchain.org"],
+  "faucets": ["https://testnet.bnbchain.org/faucet-smart"],
+  "nativeCurrency": {
+    "name": "BNB Chain Native Token",
+    "symbol": "tBNB",
+    "decimals": 18
+  },
+  "infoURL": "https://opbnb.bnbchain.org/en",
+  "shortName": "obnbt",
+  "chainId": 5611,
+  "networkId": 5611,
+  "explorers": [
+    {
+      "name": "bscscan-opbnb-testnet",
+      "url": "https://opbnb-testnet.bscscan.com",
+      "standard": "EIP3091"
+    },
+    {
+      "name": "opbnbscan",
+      "url": "http://opbnbscan.com",
+      "standard": "EIP3091"
+    }
+  ]
+}