diff --git a/tests/unit/test_exporters.py b/tests/unit/test_exporters.py
new file mode 100644
index 0000000..b71dc5f
--- /dev/null
+++ b/tests/unit/test_exporters.py
@@ -0,0 +1,158 @@
+import pytest
+import tempfile
+import subprocess
+import json
+from pathlib import Path
+from src.graph.builder import GraphBuilder, GraphType, GraphNode, NodeType
+from src.exporters.dot import DOTExporter
+from src.exporters.json_exporter import JSONExporter
+from src.exporters.png import PNGExporter
+
+
+def graphviz_available():
+    try:
+        subprocess.run(["dot", "-V"], capture_output=True, check=True)
+        return True
+    except (subprocess.CalledProcessError, FileNotFoundError):
+        return False
+
+
+class TestDOTExporter:
+    def setup_method(self):
+        self.builder = GraphBuilder(GraphType.DIRECTED)
+        self.exporter = DOTExporter(self.builder)
+
+    def test_export_creates_file(self):
+        node = GraphNode(node_id="test", node_type=NodeType.FILE, name="test.py")
+        self.builder.add_node(node)
+
+        with tempfile.NamedTemporaryFile(suffix=".dot", delete=False) as f:
+            output_path = Path(f.name)
+        try:
+            self.exporter.export(output_path)
+            assert output_path.exists()
+            content = output_path.read_text()
+            assert "digraph codegraph" in content
+            assert "test" in content
+        finally:
+            output_path.unlink()
+
+    def test_get_string_returns_dot_format(self):
+        node = GraphNode(node_id="node1", node_type=NodeType.FILE, name="file.py")
+        self.builder.add_node(node)
+
+        content = self.exporter.get_string()
+        assert "digraph codegraph" in content
+        assert "node1" in content
+
+    def test_export_with_layout(self):
+        node = GraphNode(node_id="test", node_type=NodeType.FILE, name="test.py")
+        self.builder.add_node(node)
+
+        content = self.exporter.get_string(layout="circo")
+        assert "digraph codegraph" in content
+
+    def test_export_with_rankdir(self):
+        node = GraphNode(node_id="test", node_type=NodeType.FILE, name="test.py")
+        self.builder.add_node(node)
+
+        content = self.exporter.get_string(rankdir="LR")
+        assert "rankdir=LR" in content
+
+
+class TestJSONExporter:
+    def setup_method(self):
+        self.builder = GraphBuilder(GraphType.DIRECTED)
+        self.exporter = JSONExporter(self.builder)
+
+    def test_export_creates_json_file(self):
+        node = GraphNode(node_id="test", node_type=NodeType.FILE, name="test.py")
+        self.builder.add_node(node)
+
+        with tempfile.NamedTemporaryFile(suffix=".json", delete=False) as f:
+            output_path = Path(f.name)
+        try:
+            self.exporter.export(output_path)
+            assert output_path.exists()
+            data = json.loads(output_path.read_text())
+            assert "nodes" in data
+            assert "edges" in data
+        finally:
+            output_path.unlink()
+
+    def test_get_string_returns_json(self):
+        node = GraphNode(node_id="test", node_type=NodeType.FILE, name="test.py")
+        self.builder.add_node(node)
+
+        content = self.exporter.get_string()
+        data = json.loads(content)
+        assert "nodes" in data
+        assert "edges" in data
+
+    def test_export_contains_correct_node_data(self):
+        node = GraphNode(
+            node_id="test_file",
+            node_type=NodeType.FILE,
+            name="test.py",
+            file_path=Path("/test.py"),
+            start_line=1,
+            end_line=10,
+        )
+        self.builder.add_node(node)
+
+        content = self.exporter.get_string()
+        data = json.loads(content)
+        assert len(data["nodes"]) == 1
+        assert data["nodes"][0]["name"] == "test.py"
+        assert data["nodes"][0]["type"] == "file"
+
+    def test_export_for_d3(self):
+        node = GraphNode(node_id="test", node_type=NodeType.FILE, name="test.py")
+        self.builder.add_node(node)
+
+        with tempfile.NamedTemporaryFile(suffix=".json", delete=False) as f:
+            output_path = Path(f.name)
+        try:
+            self.exporter.export_for_d3(output_path)
+            data = json.loads(output_path.read_text())
+            assert "nodes" in data
+            assert "links" in data
+        finally:
+            output_path.unlink()
+
+    def test_export_includes_statistics(self):
+        node = GraphNode(node_id="test", node_type=NodeType.FILE, name="test.py")
+        self.builder.add_node(node)
+
+        content = self.exporter.get_string()
+        data = json.loads(content)
+        assert "statistics" in data
+        assert data["statistics"]["total_nodes"] == 1
+
+
+class TestPNGExporter:
+    def setup_method(self):
+        self.builder = GraphBuilder(GraphType.DIRECTED)
+        self.exporter = PNGExporter(self.builder)
+
+    @pytest.mark.skipif(not graphviz_available(), reason="Graphviz not installed")
+    def test_export_creates_png_file(self):
+        node = GraphNode(node_id="test", node_type=NodeType.FILE, name="test.py")
+        self.builder.add_node(node)
+
+        with tempfile.NamedTemporaryFile(suffix=".png", delete=False) as f:
+            output_path = Path(f.name)
+        try:
+            self.exporter.export(output_path)
+            assert output_path.exists()
+            content = output_path.read_bytes()
+            assert len(content) > 0
+        finally:
+            if output_path.exists():
+                output_path.unlink()
+
+    def test_get_available_layouts(self):
+        layouts = self.exporter.get_available_layouts()
+        assert "dot" in layouts
+        assert "circo" in layouts
+        assert "neato" in layouts