diff --git a/tests/json.nim b/tests/json.nim
new file mode 100644
index 0000000..7bd155f
--- /dev/null
+++ b/tests/json.nim
@@ -0,0 +1,7 @@
+import ./json/testDeserialize
+import ./json/testDeserializeModes
+import ./json/testPragmas
+import ./json/testSerialize
+import ./json/testSerializeModes
+
+{.warning[UnusedImport]: off.}
diff --git a/tests/json/deserialize/objects.nim b/tests/json/deserialize/objects.nim
new file mode 100644
index 0000000..0ae8cbe
--- /dev/null
+++ b/tests/json/deserialize/objects.nim
@@ -0,0 +1,167 @@
+import std/unittest
+import pkg/serde
+import pkg/questionable
+import pkg/questionable/results
+import pkg/stew/byteutils
+
+suite "json - deserialize objects":
+  test "can deserialize json objects":
+    type MyObj = object
+      mystring: string
+      myint: int
+      myoption: ?bool
+
+    let expected = MyObj(mystring: "abc", myint: 123, myoption: some true)
+
+    let json =
+      !JsonNode.parse(
+        """{
+            "mystring": "abc",
+            "myint": 123,
+            "myoption": true
+          }"""
+      )
+
+    check !MyObj.fromJson(json) == expected
+
+  test "ignores serialize pragma when deserializing":
+    type MyObj = object
+      mystring {.serialize.}: string
+      mybool: bool
+
+    let expected = MyObj(mystring: "abc", mybool: true)
+
+    let json =
+      !JsonNode.parse(
+        """{
+            "mystring": "abc",
+            "mybool": true
+          }"""
+      )
+
+    check !MyObj.fromJson(json) == expected
+
+  test "deserializes objects with extra fields":
+    type MyObj = object
+      mystring: string
+      mybool: bool
+
+    let expected = MyObj(mystring: "abc", mybool: true)
+
+    let json =
+      !JsonNode.parse(
+        """{
+            "mystring": "abc",
+            "mybool": true,
+            "extra": "extra"
+          }"""
+      )
+    check !MyObj.fromJson(json) == expected
+
+  test "deserializes objects with less fields":
+    type MyObj = object
+      mystring: string
+      mybool: bool
+
+    let expected = MyObj(mystring: "abc", mybool: false)
+
+    let json =
+      !JsonNode.parse(
+        """{
+            "mystring": "abc"
+          }"""
+      )
+    check !MyObj.fromJson(json) == expected
+
+  test "deserializes ref objects":
+    type MyRef = ref object
+      mystring: string
+      myint: int
+
+    let expected = MyRef(mystring: "abc", myint: 1)
+
+    let json =
+      !JsonNode.parse(
+        """{
+            "mystring": "abc",
+            "myint": 1
+          }"""
+      )
+
+    let deserialized = !MyRef.fromJson(json)
+    check deserialized.mystring == expected.mystring
+    check deserialized.myint == expected.myint
+
+  test "deserializes openArray[byte]":
+    type MyRef = ref object
+      mystring: string
+      myint: int
+
+    let expected = MyRef(mystring: "abc", myint: 1)
+    let byteArray = """{
+            "mystring": "abc",
+            "myint": 1
+          }""".toBytes
+
+    let deserialized = !MyRef.fromJson(byteArray)
+    check deserialized.mystring == expected.mystring
+    check deserialized.myint == expected.myint
+
+suite "json - deserialize objects from string":
+  test "deserializes objects from string":
+    type MyObj = object
+      mystring: string
+      myint: int
+
+    let expected = MyObj(mystring: "abc", myint: 1)
+    let myObjJson =
+      """{
+            "mystring": "abc",
+            "myint": 1
+          }"""
+
+    check !MyObj.fromJson(myObjJson) == expected
+
+  test "deserializes ref objects from string":
+    type MyRef = ref object
+      mystring: string
+      myint: int
+
+    let expected = MyRef(mystring: "abc", myint: 1)
+    let myRefJson =
+      """{
+            "mystring": "abc",
+            "myint": 1
+          }"""
+
+    let deserialized = !MyRef.fromJson(myRefJson)
+    check deserialized.mystring == expected.mystring
+    check deserialized.myint == expected.myint
+
+  test "deserializes seq of objects from string":
+    type MyObj = object
+      mystring: string
+      myint: int
+
+    let expected = @[MyObj(mystring: "abc", myint: 1)]
+    let myObjsJson =
+      """[{
+            "mystring": "abc",
+            "myint": 1
+          }]"""
+
+    check !seq[MyObj].fromJson(myObjsJson) == expected
+
+  test "deserializes Option of object from string":
+    type MyObj = object
+      mystring: string
+      myint: int
+
+    let expected = some MyObj(mystring: "abc", myint: 1)
+    let myObjJson =
+      """{
+            "mystring": "abc",
+            "myint": 1
+          }"""
+
+    check !(Option[MyObj].fromJson(myObjJson)) == expected
diff --git a/tests/json/deserialize/std.nim b/tests/json/deserialize/std.nim
new file mode 100644
index 0000000..fd68a69
--- /dev/null
+++ b/tests/json/deserialize/std.nim
@@ -0,0 +1,56 @@
+import std/math
+import std/unittest
+import pkg/serde
+import pkg/questionable
+import pkg/questionable/results
+
+suite "json - deserialize std types":
+  test "deserializes NaN float":
+    check %NaN == newJString("nan")
+
+  test "deserialize enum":
+    type MyEnum = enum
+      First
+      Second
+
+    let json = newJString("Second")
+    check !MyEnum.fromJson(json) == Second
+
+  test "deserializes Option[T] when has a value":
+    let json = newJInt(1)
+    check (!fromJson(?int, json) == some 1)
+
+  test "deserializes Option[T] when doesn't have a value":
+    let json = newJNull()
+    check !fromJson(?int, json) == none int
+
+  test "deserializes float":
+    let json = newJFloat(1.234)
+    check !float.fromJson(json) == 1.234
+
+  test "deserializes Inf float":
+    let json = newJString("inf")
+    check !float.fromJson(json) == Inf
+
+  test "deserializes -Inf float":
+    let json = newJString("-inf")
+    check !float.fromJson(json) == -Inf
+
+  test "deserializes NaN float":
+    let json = newJString("nan")
+    check (!float.fromJson(json)).isNaN
+
+  test "deserializes array to sequence":
+    let expected = @[1, 2, 3]
+    let json = !JsonNode.parse("[1,2,3]")
+    check !seq[int].fromJson(json) == expected
+
+  test "deserializes uints int.high or smaller":
+    let largeUInt: uint = uint(int.high)
+    let json = newJInt(BiggestInt(largeUInt))
+    check !uint.fromJson(json) == largeUInt
+
+  test "deserializes large uints":
+    let largeUInt: uint = uint(int.high) + 1'u
+    let json = newJString($BiggestUInt(largeUInt))
+    check !uint.fromJson(json) == largeUInt
diff --git a/tests/json/deserialize/stint.nim b/tests/json/deserialize/stint.nim
new file mode 100644
index 0000000..b7428dd
--- /dev/null
+++ b/tests/json/deserialize/stint.nim
@@ -0,0 +1,72 @@
+import std/options
+import std/unittest
+import pkg/stint
+import pkg/serde
+import pkg/questionable
+import pkg/questionable/results
+
+suite "json - deserialize stint":
+  test "deserializes UInt256 from an empty JString":
+    let json = newJString("")
+    check !UInt256.fromJson(json) == 0.u256
+
+  test "deserializes UInt256 from an empty string":
+    check !UInt256.fromJson("") == 0.u256
+
+  test "deserializes ?UInt256 from an empty JString":
+    let json = newJString("")
+    check !Option[UInt256].fromJson(json) == 0.u256.some
+
+  test "deserializes ?UInt256 from an empty string":
+    check !Option[UInt256].fromJson("") == 0.u256.some
+
+  test "deserializes UInt256 from JString with no prefix":
+    let json = newJString("1")
+    check !UInt256.fromJson(json) == 1.u256
+
+  test "deserializes ?UInt256 from JString with no prefix":
+    let json = newJString("1")
+    check !Option[UInt256].fromJson(json) == 1.u256.some
+
+  test "deserializes UInt256 from string with no prefix":
+    check !UInt256.fromJson("1") == 1.u256
+
+  test "deserializes ?UInt256 from string with no prefix":
+    check !Option[UInt256].fromJson("1") == 1.u256.some
+
+  test "deserializes UInt256 from hex JString representation":
+    let json = newJString("0x1")
+    check !UInt256.fromJson(json) == 0x1.u256
+
+  test "deserializes ?UInt256 from hex JString representation":
+    let json = newJString("0x1")
+    check !Option[UInt256].fromJson(json) == 0x1.u256.some
+
+  test "deserializes ?UInt256 from hex string representation":
+    check !Option[UInt256].fromJson("0x1") == 0x1.u256.some
+
+  test "deserializes UInt256 from octal JString representation":
+    let json = newJString("0o1")
+    check !UInt256.fromJson(json) == 0o1.u256
+
+  test "deserializes ?UInt256 from octal JString representation":
+    let json = newJString("0o1")
+    check !Option[UInt256].fromJson(json) == 0o1.u256.some
+
+  test "deserializes ?UInt256 from octal string representation":
+    check !Option[UInt256].fromJson("0o1") == 0o1.u256.some
+
+  test "deserializes UInt256 from binary JString representation":
+    let json = newJString("0b1")
+    check !UInt256.fromJson(json) == 0b1.u256
+
+  test "deserializes ?UInt256 from binary JString representation":
+    let json = newJString("0b1")
+    check !Option[UInt256].fromJson(json) == 0b1.u256.some
+
+  test "deserializes ?UInt256 from binary string representation":
+    check !Option[UInt256].fromJson("0b1") == 0b1.u256.some
+
+  test "deserializes Int256 with no prefix":
+    let json = newJString("1")
+    check !Int256.fromJson(json) == 1.i256