diff --git a/package.json b/package.json
index 72a269a..f11d788 100644
--- a/package.json
+++ b/package.json
@@ -17,6 +17,7 @@
     "@testing-library/jest-dom": "^5.11.9",
     "@testing-library/react": "^11.2.5",
     "@testing-library/user-event": "^13.0.2",
+    "ajv": "^8.6.2",
     "ammo.js": "kripken/ammo.js#aab297a4164779c3a9d8dc8d9da26958de3cb778",
     "case": "^1.6.3",
     "color": "^3.1.3",
diff --git a/src/validators/Color.ts b/src/validators/Color.ts
new file mode 100644
index 0000000..21ea8f8
--- /dev/null
+++ b/src/validators/Color.ts
@@ -0,0 +1,26 @@
+import Ajv, { JSONSchemaType } from "ajv";
+import { Color } from "../helpers/colors";
+
+const ajv = new Ajv();
+
+export const ColorSchema: JSONSchemaType<Color> = {
+  $id: "https://www.owlbear.rodeo/schemas/color.json",
+  enum: [
+    "black",
+    "blue",
+    "darkGray",
+    "green",
+    "lightGray",
+    "orange",
+    "pink",
+    "primary",
+    "purple",
+    "red",
+    "teal",
+    "white",
+    "yellow",
+  ],
+  type: "string",
+};
+
+export const isColor = ajv.compile<Color>(ColorSchema);
diff --git a/src/validators/Drawing.ts b/src/validators/Drawing.ts
new file mode 100644
index 0000000..dc975db
--- /dev/null
+++ b/src/validators/Drawing.ts
@@ -0,0 +1,225 @@
+import Ajv from "ajv";
+import { Drawing } from "../types/Drawing";
+
+import { ColorSchema } from "./Color";
+import { Vector2Schema } from "./Vector2";
+
+export const DrawingSchema = {
+  $id: "https://www.owlbear.rodeo/schemas/drawing.json",
+  anyOf: [
+    {
+      $ref: "#/definitions/Shape",
+    },
+    {
+      $ref: "#/definitions/Path",
+    },
+  ],
+  definitions: {
+    PointsData: {
+      properties: {
+        points: {
+          items: {
+            $ref: "vector2.json",
+          },
+          type: "array",
+        },
+      },
+      required: ["points"],
+      type: "object",
+    },
+    RectData: {
+      properties: {
+        height: {
+          type: "number",
+        },
+        width: {
+          type: "number",
+        },
+        x: {
+          type: "number",
+        },
+        y: {
+          type: "number",
+        },
+      },
+      required: ["height", "width", "x", "y"],
+      type: "object",
+    },
+    CircleData: {
+      properties: {
+        radius: {
+          type: "number",
+        },
+        x: {
+          type: "number",
+        },
+        y: {
+          type: "number",
+        },
+      },
+      required: ["radius", "x", "y"],
+      type: "object",
+    },
+    BaseDrawing: {
+      properties: {
+        blend: {
+          type: "boolean",
+        },
+        color: {
+          $ref: "color.json",
+        },
+        id: {
+          type: "string",
+        },
+        strokeWidth: {
+          type: "number",
+        },
+      },
+      required: ["blend", "color", "id", "strokeWidth"],
+      type: "object",
+    },
+    BaseShape: {
+      allOf: [
+        {
+          $ref: "#/definitions/BaseDrawing",
+        },
+        {
+          properties: {
+            type: {
+              enum: ["shape"],
+              type: "string",
+            },
+          },
+          required: ["type"],
+          type: "object",
+        },
+      ],
+    },
+    Line: {
+      allOf: [
+        {
+          $ref: "#/definitions/BaseShape",
+        },
+        {
+          properties: {
+            data: {
+              $ref: "#/definitions/PointsData",
+            },
+            shapeType: {
+              enum: ["line"],
+              type: "string",
+            },
+          },
+          required: ["data", "shapeType"],
+          type: "object",
+        },
+      ],
+    },
+    Rectangle: {
+      allOf: [
+        {
+          $ref: "#/definitions/BaseShape",
+        },
+        {
+          properties: {
+            data: {
+              $ref: "#/definitions/RectData",
+            },
+            shapeType: {
+              enum: ["rectangle"],
+              type: "string",
+            },
+          },
+          required: ["data", "shapeType"],
+          type: "object",
+        },
+      ],
+    },
+    Circle: {
+      allOf: [
+        {
+          $ref: "#/definitions/BaseShape",
+        },
+        {
+          properties: {
+            data: {
+              $ref: "#/definitions/CircleData",
+            },
+            shapeType: {
+              enum: ["circle"],
+              type: "string",
+            },
+          },
+          required: ["data", "shapeType"],
+          type: "object",
+        },
+      ],
+    },
+    Triangle: {
+      allOf: [
+        {
+          $ref: "#/definitions/BaseShape",
+        },
+        {
+          properties: {
+            data: {
+              $ref: "#/definitions/PointsData",
+            },
+            shapeType: {
+              enum: ["triangle"],
+              type: "string",
+            },
+          },
+          required: ["data", "shapeType"],
+          type: "object",
+        },
+      ],
+    },
+    Shape: {
+      anyOf: [
+        {
+          $ref: "#/definitions/Line",
+        },
+        {
+          $ref: "#/definitions/Rectangle",
+        },
+        {
+          $ref: "#/definitions/Circle",
+        },
+        {
+          $ref: "#/definitions/Triangle",
+        },
+      ],
+    },
+    Path: {
+      allOf: [
+        {
+          $ref: "#/definitions/BaseDrawing",
+        },
+        {
+          properties: {
+            data: {
+              $ref: "#/definitions/PointsData",
+            },
+            pathType: {
+              enum: ["fill", "stroke"],
+              type: "string",
+            },
+            type: {
+              enum: ["path"],
+              type: "string",
+            },
+          },
+          required: ["data", "pathType", "type"],
+          type: "object",
+        },
+      ],
+    },
+  },
+};
+
+export const ajv = new Ajv({
+  schemas: [DrawingSchema, ColorSchema, Vector2Schema],
+});
+
+export const isDrawing = ajv.compile<Drawing>(DrawingSchema);
diff --git a/src/validators/Fog.ts b/src/validators/Fog.ts
new file mode 100644
index 0000000..72f26a5
--- /dev/null
+++ b/src/validators/Fog.ts
@@ -0,0 +1,59 @@
+import Ajv from "ajv";
+import { Fog } from "../types/Fog";
+
+import { Vector2Schema } from "./Vector2";
+import { ColorSchema } from "./Color";
+
+export const FogSchema = {
+  $id: "https://www.owlbear.rodeo/schemas/fog.json",
+  properties: {
+    color: {
+      $ref: "color.json",
+    },
+    data: {
+      $ref: "#/definitions/FogData",
+    },
+    id: {
+      type: "string",
+    },
+    strokeWidth: {
+      type: "number",
+    },
+    type: {
+      enum: ["fog"],
+      type: "string",
+    },
+    visible: {
+      type: "boolean",
+    },
+  },
+  required: ["color", "data", "id", "strokeWidth", "type", "visible"],
+  type: "object",
+  definitions: {
+    FogData: {
+      properties: {
+        holes: {
+          items: {
+            items: {
+              $ref: "vector2.json",
+            },
+            type: "array",
+          },
+          type: "array",
+        },
+        points: {
+          items: {
+            $ref: "vector2.json",
+          },
+          type: "array",
+        },
+      },
+      required: ["holes", "points"],
+      type: "object",
+    },
+  },
+};
+
+const ajv = new Ajv({ schemas: [FogSchema, ColorSchema, Vector2Schema] });
+
+export const isFog = ajv.compile<Fog>(FogSchema);
diff --git a/src/validators/MapState.ts b/src/validators/MapState.ts
new file mode 100644
index 0000000..751d92f
--- /dev/null
+++ b/src/validators/MapState.ts
@@ -0,0 +1,104 @@
+import Ajv from "ajv";
+import { MapState } from "../types/MapState";
+
+import { DrawingSchema } from "./Drawing";
+import { FogSchema } from "./Fog";
+import { NoteSchema } from "./Note";
+import { TokenStateSchema } from "./TokenState";
+import { Vector2Schema } from "./Vector2";
+import { ColorSchema } from "./Color";
+import { OutlineSchema } from "./Outline";
+
+export const MapStateSchema: any = {
+  $id: "https://www.owlbear.rodeo/schemas/map-state.json",
+  properties: {
+    tokens: {
+      $ref: "#/definitions/TokenStates",
+    },
+    drawShapes: {
+      $ref: "#/definitions/DrawingState",
+    },
+    fogShapes: {
+      $ref: "#/definitions/FogState",
+    },
+    editFlags: {
+      items: {
+        enum: ["drawing", "fog", "notes", "tokens"],
+        type: "string",
+      },
+      type: "array",
+    },
+    notes: {
+      $ref: "#/definitions/Notes",
+    },
+    mapId: {
+      type: "string",
+    },
+  },
+  required: [
+    "drawShapes",
+    "editFlags",
+    "fogShapes",
+    "mapId",
+    "notes",
+    "tokens",
+  ],
+  type: "object",
+  definitions: {
+    TokenStates: {
+      propertyNames: {
+        type: "string",
+      },
+      additionalProperties: {
+        $ref: "token-state.json",
+      },
+      required: [],
+      type: "object",
+    },
+    DrawingState: {
+      propertyNames: {
+        type: "string",
+      },
+      additionalProperties: {
+        $ref: "drawing.json",
+      },
+      required: [],
+      type: "object",
+    },
+    FogState: {
+      propertyNames: {
+        type: "string",
+      },
+      additionalProperties: {
+        $ref: "fog.json",
+      },
+      required: [],
+      type: "object",
+    },
+    Notes: {
+      propertyNames: {
+        type: "string",
+      },
+      additionalProperties: {
+        $ref: "note.json",
+      },
+      required: [],
+      type: "object",
+    },
+  },
+};
+
+export const ajv = new Ajv({
+  schemas: [
+    MapStateSchema,
+    DrawingSchema,
+    FogSchema,
+    NoteSchema,
+    TokenStateSchema,
+    Vector2Schema,
+    ColorSchema,
+    OutlineSchema,
+  ],
+});
+
+export const isMapState = ajv.compile<MapState>(MapStateSchema);
diff --git a/src/validators/Note.ts b/src/validators/Note.ts
new file mode 100644
index 0000000..a55601c
--- /dev/null
+++ b/src/validators/Note.ts
@@ -0,0 +1,62 @@
+import Ajv, { JSONSchemaType } from "ajv";
+import { Note } from "../types/Note";
+
+import { Vector2Schema } from "./Vector2";
+import { ColorSchema } from "./Color";
+
+export const NoteSchema: JSONSchemaType<Note> = {
+  $id: "https://www.owlbear.rodeo/schemas/note.json",
+  properties: {
+    color: {
+      $ref: "color.json",
+    },
+    id: {
+      type: "string",
+    },
+    lastModified: {
+      type: "number",
+    },
+    lastModifiedBy: {
+      type: "string",
+    },
+    locked: {
+      type: "boolean",
+    },
+    size: {
+      type: "number",
+    },
+    text: {
+      type: "string",
+    },
+    textOnly: {
+      type: "boolean",
+    },
+    visible: {
+      type: "boolean",
+    },
+    x: {
+      type: "number",
+    },
+    y: {
+      type: "number",
+    },
+  },
+  required: [
+    "color",
+    "id",
+    "lastModified",
+    "lastModifiedBy",
+    "locked",
+    "size",
+    "text",
+    "textOnly",
+    "visible",
+    "x",
+    "y",
+  ],
+  type: "object",
+};
+
+const ajv = new Ajv({ schemas: [NoteSchema, ColorSchema, Vector2Schema] });
+
+export const isNote = ajv.compile<Note>(NoteSchema);
diff --git a/src/validators/Outline.ts b/src/validators/Outline.ts
new file mode 100644
index 0000000..e137337
--- /dev/null
+++ b/src/validators/Outline.ts
@@ -0,0 +1,80 @@
+import Ajv from "ajv";
+import { Outline } from "../types/Outline";
+
+const ajv = new Ajv();
+
+export const OutlineSchema = {
+  $id: "https://www.owlbear.rodeo/schemas/outline.json",
+  anyOf: [
+    {
+      $ref: "#/definitions/CircleOutline",
+    },
+    {
+      $ref: "#/definitions/RectOutline",
+    },
+    {
+      $ref: "#/definitions/PathOutline",
+    },
+  ],
+  definitions: {
+    CircleOutline: {
+      properties: {
+        radius: {
+          type: "number",
+        },
+        type: {
+          enum: ["circle"],
+          type: "string",
+        },
+        x: {
+          type: "number",
+        },
+        y: {
+          type: "number",
+        },
+      },
+      required: ["radius", "type", "x", "y"],
+      type: "object",
+    },
+    RectOutline: {
+      properties: {
+        height: {
+          type: "number",
+        },
+        type: {
+          enum: ["rect"],
+          type: "string",
+        },
+        width: {
+          type: "number",
+        },
+        x: {
+          type: "number",
+        },
+        y: {
+          type: "number",
+        },
+      },
+      required: ["height", "type", "width", "x", "y"],
+      type: "object",
+    },
+    PathOutline: {
+      properties: {
+        points: {
+          items: {
+            type: "number",
+          },
+          type: "array",
+        },
+        type: {
+          enum: ["path"],
+          type: "string",
+        },
+      },
+      required: ["points", "type"],
+      type: "object",
+    },
+  },
+};
+
+export const isColor = ajv.compile<Outline>(OutlineSchema);
diff --git a/src/validators/TokenState.ts b/src/validators/TokenState.ts
new file mode 100644
index 0000000..d422420
--- /dev/null
+++ b/src/validators/TokenState.ts
@@ -0,0 +1,147 @@
+import Ajv from "ajv";
+import { TokenState } from "../types/TokenState";
+
+import { ColorSchema } from "./Color";
+import { OutlineSchema } from "./Outline";
+
+export const TokenStateSchema = {
+  $id: "https://www.owlbear.rodeo/schemas/token-state.json",
+  anyOf: [
+    {
+      $ref: "#/definitions/DefaultTokenState",
+    },
+    {
+      $ref: "#/definitions/FileTokenState",
+    },
+  ],
+  definitions: {
+    TokenCategory: {
+      enum: ["character", "prop", "vehicle"],
+      type: "string",
+    },
+    BaseTokenState: {
+      properties: {
+        category: {
+          $ref: "#/definitions/TokenCategory",
+        },
+        height: {
+          type: "number",
+        },
+        id: {
+          type: "string",
+        },
+        label: {
+          type: "string",
+        },
+        lastModified: {
+          type: "number",
+        },
+        lastModifiedBy: {
+          type: "string",
+        },
+        locked: {
+          type: "boolean",
+        },
+        outline: {
+          $ref: "outline.json",
+        },
+        owner: {
+          type: "string",
+        },
+        rotation: {
+          type: "number",
+        },
+        size: {
+          type: "number",
+        },
+        statuses: {
+          items: {
+            $ref: "color.json",
+          },
+          type: "array",
+        },
+        tokenId: {
+          type: "string",
+        },
+        visible: {
+          type: "boolean",
+        },
+        width: {
+          type: "number",
+        },
+        x: {
+          type: "number",
+        },
+        y: {
+          type: "number",
+        },
+      },
+      required: [
+        "category",
+        "height",
+        "id",
+        "label",
+        "lastModified",
+        "lastModifiedBy",
+        "locked",
+        "outline",
+        "owner",
+        "rotation",
+        "size",
+        "statuses",
+        "tokenId",
+        "visible",
+        "width",
+        "x",
+        "y",
+      ],
+      type: "object",
+    },
+    DefaultTokenState: {
+      allOf: [
+        {
+          $ref: "#/definitions/BaseTokenState",
+        },
+        {
+          properties: {
+            key: {
+              type: "string",
+            },
+            type: {
+              enum: ["default"],
+              type: "string",
+            },
+          },
+          required: ["key", "type"],
+          type: "object",
+        },
+      ],
+    },
+    FileTokenState: {
+      allOf: [
+        {
+          $ref: "#/definitions/BaseTokenState",
+        },
+        {
+          properties: {
+            file: {
+              type: "string",
+            },
+            type: {
+              enum: ["file"],
+              type: "string",
+            },
+          },
+          required: ["file", "type"],
+          type: "object",
+        },
+      ],
+    },
+  },
+};
+
+export const ajv = new Ajv({
+  schemas: [TokenStateSchema, ColorSchema, OutlineSchema],
+});
+
+export const isTokenState = ajv.compile<TokenState>(TokenStateSchema);
diff --git a/src/validators/Vector2.ts b/src/validators/Vector2.ts
new file mode 100644
index 0000000..40d01cb
--- /dev/null
+++ b/src/validators/Vector2.ts
@@ -0,0 +1,20 @@
+import Ajv, { JSONSchemaType } from "ajv";
+import Vector2 from "../helpers/Vector2";
+
+const ajv = new Ajv();
+
+export const Vector2Schema: JSONSchemaType<Vector2> = {
+  $id: "https://www.owlbear.rodeo/schemas/vector2.json",
+  properties: {
+    x: {
+      type: "number",
+    },
+    y: {
+      type: "number",
+    },
+  },
+  required: ["x", "y"],
+  type: "object",
+};
+
+export const isColor = ajv.compile<Vector2>(Vector2Schema);
diff --git a/yarn.lock b/yarn.lock
index 962b452..f686e89 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3686,6 +3686,16 @@ ajv@^6.1.0, ajv@^6.10.0, ajv@^6.10.2, ajv@^6.12.3, ajv@^6.12.4, ajv@^6.12.5:
     json-schema-traverse "^0.4.1"
     uri-js "^4.2.2"
 
+ajv@^8.6.2:
+  version "8.6.2"
+  resolved "https://registry.yarnpkg.com/ajv/-/ajv-8.6.2.tgz#2fb45e0e5fcbc0813326c1c3da535d1881bb0571"
+  integrity sha512-9807RlWAgT564wT+DjeyU5OFMPjmzxVobvDFmNAhY+5zD6A2ly3jDp6sgnfyDtlIQ+7H97oc/DGCzzfu9rjw9w==
+  dependencies:
+    fast-deep-equal "^3.1.1"
+    json-schema-traverse "^1.0.0"
+    require-from-string "^2.0.2"
+    uri-js "^4.2.2"
+
 alphanum-sort@^1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/alphanum-sort/-/alphanum-sort-1.0.2.tgz#97a1119649b211ad33691d9f9f486a8ec9fbe0a3"
@@ -8663,6 +8673,11 @@ json-schema-traverse@^0.4.1:
   resolved "https://registry.yarnpkg.com/json-schema-traverse/-/json-schema-traverse-0.4.1.tgz#69f6a87d9513ab8bb8fe63bdb0979c448e684660"
   integrity sha512-xbbCH5dCYU5T8LcEhhuh7HJ88HXuW3qsI3Y0zOZFKfZEHcpWiHU/Jxzk629Brsab/mMiHQti9wMP+845RPe3Vg==
 
+json-schema-traverse@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/json-schema-traverse/-/json-schema-traverse-1.0.0.tgz#ae7bcb3656ab77a73ba5c49bf654f38e6b6860e2"
+  integrity sha512-NM8/P9n3XjXhIZn1lLhkFaACTOURQXjWhV4BA/RnOv8xvgqtqpAX9IO4mRQxSx1Rlo4tqzeqb0sOlruaOy3dug==
+
 json-schema@0.2.3:
   version "0.2.3"
   resolved "https://registry.yarnpkg.com/json-schema/-/json-schema-0.2.3.tgz#b480c892e59a2f05954ce727bd3f2a4e882f9e13"
@@ -11759,6 +11774,11 @@ require-directory@^2.1.1:
   resolved "https://registry.yarnpkg.com/require-directory/-/require-directory-2.1.1.tgz#8c64ad5fd30dab1c976e2344ffe7f792a6a6df42"
   integrity sha1-jGStX9MNqxyXbiNE/+f3kqam30I=
 
+require-from-string@^2.0.2:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/require-from-string/-/require-from-string-2.0.2.tgz#89a7fdd938261267318eafe14f9c32e598c36909"
+  integrity sha512-Xf0nWe6RseziFMu+Ap9biiUbmplq6S9/p+7w7YXP/JBHhrUDDUhwa+vANyubuqfZWTveU//DYVGsDG7RKL/vEw==
+
 require-main-filename@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/require-main-filename/-/require-main-filename-2.0.0.tgz#d0b329ecc7cc0f61649f62215be69af54aa8989b"