diff --git a/eth-rpc/server/jsonconverters.nim b/eth-rpc/server/jsonconverters.nim
new file mode 100644
index 0000000..43d5889
--- /dev/null
+++ b/eth-rpc/server/jsonconverters.nim
@@ -0,0 +1,25 @@
+import json, stint
+
+iterator bytes*(i: UInt256|Int256): byte =
+  let b = cast[ptr array[32, byte]](i.unsafeaddr)
+  var pos = 0
+  while pos < 32:
+    yield b[pos]
+    pos += 1
+
+proc `%`*(n: UInt256): JsonNode =
+  ## Generic constructor for JSON data. Creates a new `JInt JsonNode`.
+  result = newJArray()
+  for elem in n.bytes:
+    result.add(%int(elem))
+
+proc `%`*(n: Int256): JsonNode =
+  ## Generic constructor for JSON data. Creates a new `JInt JsonNode`.
+  result = newJArray()
+  for elem in n.bytes:
+    result.add(%int(elem))
+
+proc `%`*(n: byte): JsonNode =
+  ## Generic constructor for JSON data. Creates a new `JInt JsonNode`.
+  result = newJInt(int(n))
+