diff --git a/cmd/ocap-webserver/main.go b/cmd/ocap-webserver/main.go
index f4b34e61..255a7e1d 100644
--- a/cmd/ocap-webserver/main.go
+++ b/cmd/ocap-webserver/main.go
@@ -123,11 +123,14 @@ func showConversionStatus(ctx context.Context, repo *server.RepoOperation) error
 }
 
 func convertSingleFile(ctx context.Context, repo *server.RepoOperation, inputFile, dataDir string, chunkSize uint32, format string) error {
-	// Determine filename - only strip .gz to match database filename format
+	// Determine filename - strip .gz and .json to get base name
 	baseName := filepath.Base(inputFile)
 	if ext := filepath.Ext(baseName); ext == ".gz" {
 		baseName = baseName[:len(baseName)-len(ext)]
 	}
+	if ext := filepath.Ext(baseName); ext == ".json" {
+		baseName = baseName[:len(baseName)-len(ext)]
+	}
 
 	// Check if operation exists in database - if so, use worker for consistent behavior
 	if op, err := repo.GetByFilename(ctx, baseName); err == nil && op != nil {
diff --git a/cmd/ocap-webserver/main_test.go b/cmd/ocap-webserver/main_test.go
index 02b4ba8d..035a1113 100644
--- a/cmd/ocap-webserver/main_test.go
+++ b/cmd/ocap-webserver/main_test.go
@@ -281,8 +281,8 @@ func TestConvertSingleFile(t *testing.T) {
 	err = convertSingleFile(ctx, repo, inputPath, dataDir, 300, "protobuf")
 	require.NoError(t, err)
 
-	// Verify output was created (keeps .json suffix to match database filename)
-	outputDir := filepath.Join(dataDir, "test_mission.json")
+	// Verify output was created
+	outputDir := filepath.Join(dataDir, "test_mission")
 	_, err = os.Stat(filepath.Join(outputDir, "manifest.pb"))
 	require.NoError(t, err)
 }
@@ -359,7 +359,7 @@ func TestConvertSingleFile_WithDatabaseEntry(t *testing.T) {
 		WorldName:        "Stratis",
 		MissionName:      "Test Op",
 		MissionDuration:  10,
-		Filename:         "db_test.json",
+		Filename:         "db_test",
 		Date:             "2024-01-01",
 		StorageFormat:    "json",
 		ConversionStatus: "pending",
@@ -375,12 +375,12 @@ func TestConvertSingleFile_WithDatabaseEntry(t *testing.T) {
 	require.NoError(t, err)
 
 	// Verify output was created
-	outputDir := filepath.Join(dataDir, "db_test.json")
+	outputDir := filepath.Join(dataDir, "db_test")
 	_, err = os.Stat(filepath.Join(outputDir, "manifest.pb"))
 	require.NoError(t, err)
 
 	// Verify database was updated
-	result, err := repo.GetByFilename(ctx, "db_test.json")
+	result, err := repo.GetByFilename(ctx, "db_test")
 	require.NoError(t, err)
 	assert.Equal(t, "completed", result.ConversionStatus)
 	assert.Equal(t, "protobuf", result.StorageFormat)
@@ -449,7 +449,7 @@ func TestConvertAll_WithOperations(t *testing.T) {
 	}`
 
 	// Write gzipped JSON
-	jsonPath := filepath.Join(dataDir, "test_op.gz")
+	jsonPath := filepath.Join(dataDir, "test_op.json.gz")
 	f, err := os.Create(jsonPath)
 	require.NoError(t, err)
 	gw := gzip.NewWriter(f)
diff --git a/internal/conversion/worker.go b/internal/conversion/worker.go
index 20a3e8b0..b2c3c555 100644
--- a/internal/conversion/worker.go
+++ b/internal/conversion/worker.go
@@ -174,7 +174,7 @@ func (w *Worker) convertOperation(ctx context.Context, op Operation) error {
 	}
 
 	// Determine paths
-	jsonPath := filepath.Join(w.dataDir, op.Filename+".gz")
+	jsonPath := filepath.Join(w.dataDir, op.Filename+".json.gz")
 	outputPath := filepath.Join(w.dataDir, op.Filename)
 
 	// Check if JSON file exists
diff --git a/internal/conversion/worker_test.go b/internal/conversion/worker_test.go
index 5be0d24c..871b3025 100644
--- a/internal/conversion/worker_test.go
+++ b/internal/conversion/worker_test.go
@@ -112,7 +112,7 @@ func TestWorker_ConvertOne(t *testing.T) {
 	}`
 
 	// Write gzipped JSON file
-	jsonPath := filepath.Join(dir, "test_mission.gz")
+	jsonPath := filepath.Join(dir, "test_mission.json.gz")
 	f, err := os.Create(jsonPath)
 	assert.NoError(t, err)
 	gw := gzip.NewWriter(f)
@@ -161,7 +161,7 @@ func TestWorker_ProcessOnce(t *testing.T) {
 
 	// Write gzipped JSON files
 	for _, name := range []string{"mission1", "mission2"} {
-		jsonPath := filepath.Join(dir, name+".gz")
+		jsonPath := filepath.Join(dir, name+".json.gz")
 		f, _ := os.Create(jsonPath)
 		gw := gzip.NewWriter(f)
 		gw.Write([]byte(testData))
@@ -303,7 +303,7 @@ func TestTriggerConversion(t *testing.T) {
 	}`
 
 	// Write gzipped JSON file
-	jsonPath := filepath.Join(dir, "trigger_mission.gz")
+	jsonPath := filepath.Join(dir, "trigger_mission.json.gz")
 	f, err := os.Create(jsonPath)
 	assert.NoError(t, err)
 	gw := gzip.NewWriter(f)
@@ -397,7 +397,7 @@ func TestWorker_FlatBuffersFormat(t *testing.T) {
 	}`
 
 	// Write gzipped JSON file
-	jsonPath := filepath.Join(dir, "fb_test.gz")
+	jsonPath := filepath.Join(dir, "fb_test.json.gz")
 	f, err := os.Create(jsonPath)
 	assert.NoError(t, err)
 	gw := gzip.NewWriter(f)
@@ -442,7 +442,7 @@ func TestWorker_ContextCancellation(t *testing.T) {
 
 	// Write multiple gzipped JSON files
 	for i := 1; i <= 3; i++ {
-		jsonPath := filepath.Join(dir, fmt.Sprintf("cancel_%d.gz", i))
+		jsonPath := filepath.Join(dir, fmt.Sprintf("cancel_%d.json.gz", i))
 		f, _ := os.Create(jsonPath)
 		gw := gzip.NewWriter(f)
 		gw.Write([]byte(testData))
@@ -613,7 +613,7 @@ func TestConvertOperation_UpdateConvertingStatusError(t *testing.T) {
 
 	// Create test JSON file
 	testData := `{"worldName": "test", "missionName": "Test", "endFrame": 5, "captureDelay": 1, "entities": [], "events": [], "times": []}`
-	jsonPath := filepath.Join(dir, "test.gz")
+	jsonPath := filepath.Join(dir, "test.json.gz")
 	f, _ := os.Create(jsonPath)
 	gw := gzip.NewWriter(f)
 	gw.Write([]byte(testData))
@@ -640,7 +640,7 @@ func TestConvertOperation_UpdateStorageFormatError(t *testing.T) {
 
 	// Create test JSON file
 	testData := `{"worldName": "test", "missionName": "Test", "endFrame": 5, "captureDelay": 1, "entities": [], "events": [], "times": []}`
-	jsonPath := filepath.Join(dir, "test.gz")
+	jsonPath := filepath.Join(dir, "test.json.gz")
 	f, _ := os.Create(jsonPath)
 	gw := gzip.NewWriter(f)
 	gw.Write([]byte(testData))
@@ -666,7 +666,7 @@ func TestConvertOperation_UpdateCompletedStatusError(t *testing.T) {
 
 	// Create test JSON file
 	testData := `{"worldName": "test", "missionName": "Test", "endFrame": 5, "captureDelay": 1, "entities": [], "events": [], "times": []}`
-	jsonPath := filepath.Join(dir, "test.gz")
+	jsonPath := filepath.Join(dir, "test.json.gz")
 	f, _ := os.Create(jsonPath)
 	gw := gzip.NewWriter(f)
 	gw.Write([]byte(testData))
@@ -693,7 +693,7 @@ func TestConvertOperation_UpdateDurationError(t *testing.T) {
 
 	// Create test JSON file
 	testData := `{"worldName": "test", "missionName": "Test", "endFrame": 5, "captureDelay": 1, "entities": [], "events": [], "times": []}`
-	jsonPath := filepath.Join(dir, "test.gz")
+	jsonPath := filepath.Join(dir, "test.json.gz")
 	f, _ := os.Create(jsonPath)
 	gw := gzip.NewWriter(f)
 	gw.Write([]byte(testData))
@@ -720,7 +720,7 @@ func TestConvertOperation_InvalidStorageFormat(t *testing.T) {
 
 	// Create test JSON file
 	testData := `{"worldName": "test", "missionName": "Test", "endFrame": 5, "captureDelay": 1, "entities": [], "events": [], "times": []}`
-	jsonPath := filepath.Join(dir, "test.gz")
+	jsonPath := filepath.Join(dir, "test.json.gz")
 	f, _ := os.Create(jsonPath)
 	gw := gzip.NewWriter(f)
 	gw.Write([]byte(testData))
diff --git a/internal/server/handler.go b/internal/server/handler.go
index eb9031a8..29637db7 100644
--- a/internal/server/handler.go
+++ b/internal/server/handler.go
@@ -362,7 +362,9 @@ func (h *Handler) StoreOperation(c echo.Context) error {
 		return echo.ErrForbidden
 	}
 
-	filename := strings.TrimSuffix(filepath.Base(c.FormValue("filename")), ".gz")
+	filename := filepath.Base(c.FormValue("filename"))
+	filename = strings.TrimSuffix(filename, ".gz")
+	filename = strings.TrimSuffix(filename, ".json")
 
 	op := Operation{
 		WorldName:   c.FormValue("worldName"),
@@ -391,7 +393,7 @@ func (h *Handler) StoreOperation(c echo.Context) error {
 	}
 	defer file.Close()
 
-	writer, err := os.Create(filepath.Join(h.setting.Data, filename+".gz"))
+	writer, err := os.Create(filepath.Join(h.setting.Data, filename+".json.gz"))
 	if err != nil {
 		return err
 	}
@@ -414,7 +416,7 @@ func (h *Handler) GetCapture(c echo.Context) error {
 		return err
 	}
 
-	upath := filepath.Join(h.setting.Data, filepath.Base(name+".gz"))
+	upath := filepath.Join(h.setting.Data, filepath.Base(name+".json.gz"))
 
 	c.Response().Header().Set("Content-Encoding", "gzip")
 	c.Response().Header().Set("Content-Type", "application/json")
@@ -428,7 +430,7 @@ func (h *Handler) GetCaptureFile(c echo.Context) error {
 		return err
 	}
 
-	filename := filepath.Base(name + ".gz")
+	filename := filepath.Base(name + ".json.gz")
 
 	c.Response().Header().Set("Content-Disposition", "attachment;filename=\""+filename+"\"")
 
diff --git a/internal/server/handler_test.go b/internal/server/handler_test.go
index c673198c..2f5f24b9 100644
--- a/internal/server/handler_test.go
+++ b/internal/server/handler_test.go
@@ -232,7 +232,7 @@ func TestGetOperationManifest(t *testing.T) {
 		"times": [],
 		"Ede": []
 	}`
-	testDataPath := filepath.Join(dataDir, "test_mission.gz")
+	testDataPath := filepath.Join(dataDir, "test_mission.json.gz")
 	err = writeGzipped(testDataPath, []byte(testData))
 	assert.NoError(t, err)
 
@@ -731,7 +731,7 @@ func TestStoreOperation(t *testing.T) {
 		writer.WriteField("tag", "coop")
 
 		// Create file part
-		fileWriter, err := writer.CreateFormFile("file", "test_upload.gz")
+		fileWriter, err := writer.CreateFormFile("file", "test_upload.json.gz")
 		require.NoError(t, err)
 
 		// Write gzipped JSON data
@@ -752,7 +752,7 @@ func TestStoreOperation(t *testing.T) {
 		assert.Equal(t, http.StatusOK, rec.Code)
 
 		// Verify file was created
-		_, err = os.Stat(filepath.Join(dataDir, "test_upload.gz"))
+		_, err = os.Stat(filepath.Join(dataDir, "test_upload.json.gz"))
 		assert.NoError(t, err)
 	})
 
@@ -798,7 +798,7 @@ func TestGetCapture(t *testing.T) {
 
 	// Create test gzipped file
 	testData := `{"test": "capture data"}`
-	testPath := filepath.Join(dataDir, "test_capture.gz")
+	testPath := filepath.Join(dataDir, "test_capture.json.gz")
 	err = writeGzipped(testPath, []byte(testData))
 	require.NoError(t, err)
 
@@ -841,7 +841,7 @@ func TestGetCaptureFile(t *testing.T) {
 	require.NoError(t, err)
 
 	// Create test gzipped file
-	testPath := filepath.Join(dataDir, "download_test.gz")
+	testPath := filepath.Join(dataDir, "download_test.json.gz")
 	err = writeGzipped(testPath, []byte(`{"download": "test"}`))
 	require.NoError(t, err)
 
@@ -859,7 +859,7 @@ func TestGetCaptureFile(t *testing.T) {
 	err = hdlr.GetCaptureFile(c)
 	assert.NoError(t, err)
 	assert.Contains(t, rec.Header().Get("Content-Disposition"), "attachment")
-	assert.Contains(t, rec.Header().Get("Content-Disposition"), "download_test.gz")
+	assert.Contains(t, rec.Header().Get("Content-Disposition"), "download_test.json.gz")
 }
 
 func TestGetMapTitle(t *testing.T) {
@@ -1107,7 +1107,7 @@ func TestStoreOperationWithConversionTrigger(t *testing.T) {
 	writer.WriteField("filename", "trigger_test")
 	writer.WriteField("tag", "coop")
 
-	fileWriter, _ := writer.CreateFormFile("file", "trigger_test.gz")
+	fileWriter, _ := writer.CreateFormFile("file", "trigger_test.json.gz")
 	gw := gzip.NewWriter(fileWriter)
 	gw.Write([]byte(`{"test": "trigger"}`))
 	gw.Close()
@@ -1415,7 +1415,7 @@ func TestGetOperationManifest_JSONFormat(t *testing.T) {
 		"entities": [],
 		"events": []
 	}`
-	err = writeGzipped(filepath.Join(dataDir, "json_manifest_test.gz"), []byte(testJSON))
+	err = writeGzipped(filepath.Join(dataDir, "json_manifest_test.json.gz"), []byte(testJSON))
 	require.NoError(t, err)
 
 	// Register JSON engine
@@ -1680,7 +1680,7 @@ func TestStoreOperation_InvalidMissionDuration(t *testing.T) {
 	writer.WriteField("filename", "invalid_duration_test")
 	writer.WriteField("tag", "coop")
 
-	fileWriter, _ := writer.CreateFormFile("file", "test.gz")
+	fileWriter, _ := writer.CreateFormFile("file", "test.json.gz")
 	gw := gzip.NewWriter(fileWriter)
 	gw.Write([]byte(`{"test": "data"}`))
 	gw.Close()
@@ -1725,7 +1725,7 @@ func TestStoreOperation_WrongSecret(t *testing.T) {
 	writer.WriteField("filename", "wrong_secret_test")
 	writer.WriteField("tag", "coop")
 
-	fileWriter, _ := writer.CreateFormFile("file", "test.gz")
+	fileWriter, _ := writer.CreateFormFile("file", "test.json.gz")
 	gw := gzip.NewWriter(fileWriter)
 	gw.Write([]byte(`{"test": "data"}`))
 	gw.Close()
diff --git a/internal/server/integration_test.go b/internal/server/integration_test.go
index d99f79d9..c4fcae1b 100644
--- a/internal/server/integration_test.go
+++ b/internal/server/integration_test.go
@@ -97,7 +97,7 @@ func TestIntegration_ConversionAndPlayback(t *testing.T) {
 	}
 
 	// Write gzipped JSON file
-	jsonPath := filepath.Join(dataDir, "test_integration.gz")
+	jsonPath := filepath.Join(dataDir, "test_integration.json.gz")
 	writeTestGzippedJSON(t, jsonPath, testRecording)
 
 	// Store operation in database
diff --git a/internal/storage/json.go b/internal/storage/json.go
index 20b1be93..b5ef6d47 100644
--- a/internal/storage/json.go
+++ b/internal/storage/json.go
@@ -87,7 +87,7 @@ func (e *JSONEngine) Convert(ctx context.Context, jsonPath, outputPath string) e
 
 func (e *JSONEngine) loadJSON(filename string) (map[string]interface{}, error) {
 	// Try gzipped first
-	path := filepath.Join(e.dataDir, filename+".gz")
+	path := filepath.Join(e.dataDir, filename+".json.gz")
 	if _, err := os.Stat(path); err == nil {
 		return e.loadGzipJSON(path)
 	}
diff --git a/internal/storage/json_test.go b/internal/storage/json_test.go
index cc071ddb..cc6a874e 100644
--- a/internal/storage/json_test.go
+++ b/internal/storage/json_test.go
@@ -80,7 +80,7 @@ func TestJSONEngineGetManifestGzipped(t *testing.T) {
 		]
 	}`
 
-	gzPath := filepath.Join(dir, "gztest.gz")
+	gzPath := filepath.Join(dir, "gztest.json.gz")
 	f, err := os.Create(gzPath)
 	require.NoError(t, err)
 
@@ -191,7 +191,7 @@ func TestJSONEngineInvalidGzip(t *testing.T) {
 	dir := t.TempDir()
 
 	// Create a file with .gz extension but invalid gzip data
-	invalidGzPath := filepath.Join(dir, "invalid.gz")
+	invalidGzPath := filepath.Join(dir, "invalid.json.gz")
 	err := os.WriteFile(invalidGzPath, []byte("not valid gzip data"), 0644)
 	require.NoError(t, err)
 
@@ -204,7 +204,7 @@ func TestJSONEngineInvalidJSONInGzip(t *testing.T) {
 	dir := t.TempDir()
 
 	// Create gzipped file with invalid JSON content
-	gzPath := filepath.Join(dir, "badjson.gz")
+	gzPath := filepath.Join(dir, "badjson.json.gz")
 	f, err := os.Create(gzPath)
 	require.NoError(t, err)