diff --git a/src/store/execution/__tests__/splitGridExecutor.test.ts b/src/store/execution/__tests__/splitGridExecutor.test.ts
new file mode 100644
index 00000000..2ad0bf16
--- /dev/null
+++ b/src/store/execution/__tests__/splitGridExecutor.test.ts
@@ -0,0 +1,170 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { executeSplitGrid } from "../splitGridExecutor";
+import type { NodeExecutionContext } from "../types";
+import type { WorkflowNode } from "@/types";
+
+// Mock gridSplitter
+vi.mock("@/utils/gridSplitter", () => ({
+  splitWithDimensions: vi.fn().mockResolvedValue({
+    images: ["split-0.png", "split-1.png", "split-2.png", "split-3.png"],
+  }),
+}));
+
+// Mock Image constructor for dimension loading
+class MockImage {
+  width = 512;
+  height = 512;
+  onload: (() => void) | null = null;
+  onerror: (() => void) | null = null;
+  private _src = "";
+  get src() { return this._src; }
+  set src(val: string) {
+    this._src = val;
+    // Use queueMicrotask so onload fires after assignment
+    queueMicrotask(() => this.onload?.());
+  }
+}
+vi.stubGlobal("Image", MockImage);
+
+const defaultProviderSettings = {
+  providers: {
+    gemini: { apiKey: "" },
+    replicate: { apiKey: "" },
+    fal: { apiKey: "" },
+    kie: { apiKey: "" },
+    wavespeed: { apiKey: "" },
+    openai: { apiKey: "" },
+  },
+} as any;
+
+function makeNode(data: Record<string, unknown> = {}): WorkflowNode {
+  return {
+    id: "sg-1",
+    type: "splitGrid",
+    position: { x: 0, y: 0 },
+    data: {
+      sourceImage: null,
+      status: null,
+      error: null,
+      gridRows: 2,
+      gridCols: 2,
+      isConfigured: true,
+      childNodeIds: [
+        { imageInput: "child-0" },
+        { imageInput: "child-1" },
+        { imageInput: "child-2" },
+        { imageInput: "child-3" },
+      ],
+      ...data,
+    },
+  } as WorkflowNode;
+}
+
+function makeCtx(
+  node: WorkflowNode,
+  overrides: Partial<NodeExecutionContext> = {}
+): NodeExecutionContext {
+  return {
+    node,
+    getConnectedInputs: vi.fn().mockReturnValue({
+      images: ["data:image/png;base64,source"],
+      videos: [],
+      audio: [],
+      text: null,
+      dynamicInputs: {},
+      easeCurve: null,
+    }),
+    updateNodeData: vi.fn(),
+    getFreshNode: vi.fn().mockReturnValue(node),
+    getEdges: vi.fn().mockReturnValue([]),
+    getNodes: vi.fn().mockReturnValue([node]),
+    providerSettings: defaultProviderSettings,
+    addIncurredCost: vi.fn(),
+    addToGlobalHistory: vi.fn(),
+    generationsPath: null,
+    saveDirectoryPath: null,
+    get: vi.fn(),
+    ...overrides,
+  };
+}
+
+beforeEach(() => {
+  vi.clearAllMocks();
+});
+
+describe("executeSplitGrid", () => {
+  it("should throw when no input image connected", async () => {
+    const node = makeNode();
+    const ctx = makeCtx(node, {
+      getConnectedInputs: vi.fn().mockReturnValue({
+        images: [],
+        videos: [],
+        audio: [],
+        text: null,
+        dynamicInputs: {},
+        easeCurve: null,
+      }),
+    });
+
+    await expect(executeSplitGrid(ctx)).rejects.toThrow("No input image connected");
+  });
+
+  it("should throw when not configured", async () => {
+    const node = makeNode({ isConfigured: false });
+    const ctx = makeCtx(node);
+
+    await expect(executeSplitGrid(ctx)).rejects.toThrow("Node not configured");
+  });
+
+  it("should set loading status", async () => {
+    const node = makeNode();
+    const ctx = makeCtx(node);
+
+    await executeSplitGrid(ctx);
+
+    const calls = (ctx.updateNodeData as ReturnType<typeof vi.fn>).mock.calls;
+    const loadingCall = calls.find(
+      (c: unknown[]) => (c[1] as Record<string, unknown>).status === "loading"
+    );
+    expect(loadingCall).toBeDefined();
+  });
+
+  it("should set complete status on success", async () => {
+    const node = makeNode();
+    const ctx = makeCtx(node);
+
+    await executeSplitGrid(ctx);
+
+    const calls = (ctx.updateNodeData as ReturnType<typeof vi.fn>).mock.calls;
+    const completeCall = calls.find(
+      (c: unknown[]) => (c[1] as Record<string, unknown>).status === "complete"
+    );
+    expect(completeCall).toBeDefined();
+  });
+
+  it("should update child imageInput nodes with split images", async () => {
+    const node = makeNode();
+    const ctx = makeCtx(node);
+
+    await executeSplitGrid(ctx);
+
+    // Check that child nodes were updated
+    expect(ctx.updateNodeData).toHaveBeenCalledWith("child-0", expect.objectContaining({
+      image: "split-0.png",
+    }));
+    expect(ctx.updateNodeData).toHaveBeenCalledWith("child-1", expect.objectContaining({
+      image: "split-1.png",
+    }));
+  });
+
+  it("should set source image on node", async () => {
+    const node = makeNode();
+    const ctx = makeCtx(node);
+
+    await executeSplitGrid(ctx);
+
+    expect(ctx.updateNodeData).toHaveBeenCalledWith("sg-1", expect.objectContaining({
+      sourceImage: "data:image/png;base64,source",
+    }));
+  });
+});
diff --git a/src/store/execution/splitGridExecutor.ts b/src/store/execution/splitGridExecutor.ts
new file mode 100644
index 00000000..68375c1a
--- /dev/null
+++ b/src/store/execution/splitGridExecutor.ts
@@ -0,0 +1,69 @@
+/**
+ * SplitGrid Executor
+ *
+ * Unified executor for splitGrid nodes.
+ * Splits an input image into grid cells and populates child imageInput nodes.
+ */
+
+import type { SplitGridNodeData } from "@/types";
+import type { NodeExecutionContext } from "./types";
+
+export async function executeSplitGrid(ctx: NodeExecutionContext): Promise<void> {
+  const { node, getConnectedInputs, updateNodeData } = ctx;
+
+  const { images } = getConnectedInputs(node.id);
+  const sourceImage = images[0] || null;
+
+  if (!sourceImage) {
+    updateNodeData(node.id, {
+      status: "error",
+      error: "No input image connected",
+    });
+    throw new Error("No input image connected");
+  }
+
+  const nodeData = node.data as SplitGridNodeData;
+
+  if (!nodeData.isConfigured) {
+    updateNodeData(node.id, {
+      status: "error",
+      error: "Node not configured - open settings first",
+    });
+    throw new Error("Node not configured - open settings first");
+  }
+
+  updateNodeData(node.id, {
+    sourceImage,
+    status: "loading",
+    error: null,
+  });
+
+  const { splitWithDimensions } = await import("@/utils/gridSplitter");
+  const { images: splitImages } = await splitWithDimensions(
+    sourceImage,
+    nodeData.gridRows,
+    nodeData.gridCols
+  );
+
+  // Populate child imageInput nodes with split images
+  for (let index = 0; index < nodeData.childNodeIds.length; index++) {
+    const childSet = nodeData.childNodeIds[index];
+    if (splitImages[index]) {
+      await new Promise<void>((resolve) => {
+        const img = new Image();
+        img.onload = () => {
+          updateNodeData(childSet.imageInput, {
+            image: splitImages[index],
+            filename: `split-${Math.floor(index / nodeData.gridCols) + 1}-${(index % nodeData.gridCols) + 1}.png`,
+            dimensions: { width: img.width, height: img.height },
+          });
+          resolve();
+        };
+        img.onerror = () => resolve();
+        img.src = splitImages[index];
+      });
+    }
+  }
+
+  updateNodeData(node.id, { status: "complete", error: null });
+}