diff --git a/pyzebra/app/panel_ccl_integrate.py b/pyzebra/app/panel_ccl_integrate.py
index 45d3dc4..317785c 100644
--- a/pyzebra/app/panel_ccl_integrate.py
+++ b/pyzebra/app/panel_ccl_integrate.py
@@ -311,8 +311,8 @@ def create():
     merge_button = Button(label="Merge scans", width=145)
     merge_button.on_click(merge_button_callback)
 
-    integ_from = Spinner(title="Integrate from:", default_size=145, disabled=True)
-    integ_to = Spinner(title="to:", default_size=145, disabled=True)
+    fit_from_spinner = Spinner(title="Fit from:", default_size=145)
+    fit_to_spinner = Spinner(title="to:", default_size=145)
 
     def fitparams_add_dropdown_callback(click):
         # bokeh requires (str, str) for MultiSelect options
@@ -416,7 +416,9 @@ def create():
 
     def fit_all_button_callback():
         for scan in det_data:
-            pyzebra.fit_scan(scan, fit_params)
+            pyzebra.fit_scan(
+                scan, fit_params, fit_from=fit_from_spinner.value, fit_to=fit_to_spinner.value
+            )
 
         _update_plot(_get_selected_scan())
         _update_table()
@@ -426,7 +428,9 @@ def create():
 
     def fit_button_callback():
         scan = _get_selected_scan()
-        pyzebra.fit_scan(scan, fit_params)
+        pyzebra.fit_scan(
+            scan, fit_params, fit_from=fit_from_spinner.value, fit_to=fit_to_spinner.value
+        )
 
         _update_plot(scan)
         _update_table()
@@ -514,7 +518,7 @@ def create():
         fitparams_table,
         Spacer(width=20),
         column(
-            row(integ_from, integ_to),
+            row(fit_from_spinner, fit_to_spinner),
             row(bin_size_spinner, column(Spacer(height=19), lorentz_toggle)),
             row(area_method_radiobutton),
             row(fit_button, fit_all_button),
diff --git a/pyzebra/app/panel_param_study.py b/pyzebra/app/panel_param_study.py
index b96e5ff..d2d9f59 100644
--- a/pyzebra/app/panel_param_study.py
+++ b/pyzebra/app/panel_param_study.py
@@ -414,8 +414,8 @@ def create():
     )
     param_select.on_change("value", param_select_callback)
 
-    integ_from = Spinner(title="Integrate from:", default_size=145, disabled=True)
-    integ_to = Spinner(title="to:", default_size=145, disabled=True)
+    fit_from_spinner = Spinner(title="Fit from:", default_size=145)
+    fit_to_spinner = Spinner(title="to:", default_size=145)
 
     def fitparams_add_dropdown_callback(click):
         # bokeh requires (str, str) for MultiSelect options
@@ -518,7 +518,9 @@ def create():
 
     def fit_all_button_callback():
         for scan in det_data:
-            pyzebra.fit_scan(scan, fit_params)
+            pyzebra.fit_scan(
+                scan, fit_params, fit_from=fit_from_spinner.value, fit_to=fit_to_spinner.value
+            )
 
         _update_plot()
         _update_table()
@@ -528,7 +530,9 @@ def create():
 
     def fit_button_callback():
         scan = _get_selected_scan()
-        pyzebra.fit_scan(scan, fit_params)
+        pyzebra.fit_scan(
+            scan, fit_params, fit_from=fit_from_spinner.value, fit_to=fit_to_spinner.value
+        )
 
         _update_plot()
         _update_table()
@@ -610,7 +614,7 @@ def create():
         fitparams_table,
         Spacer(width=20),
         column(
-            row(integ_from, integ_to),
+            row(fit_from_spinner, fit_to_spinner),
             row(bin_size_spinner, column(Spacer(height=19), lorentz_toggle)),
             row(area_method_radiobutton),
             row(fit_button, fit_all_button),
diff --git a/pyzebra/ccl_process.py b/pyzebra/ccl_process.py
index 01a3bed..3ccd7e1 100644
--- a/pyzebra/ccl_process.py
+++ b/pyzebra/ccl_process.py
@@ -87,10 +87,20 @@ def merge_scans(scan1, scan2):
     print(f'Merging scans: {scan1["idx"]} ({fname1}) <-- {scan2["idx"]} ({fname2})')
 
 
-def fit_scan(scan, model_dict):
+def fit_scan(scan, model_dict, fit_from=None, fit_to=None):
+    if fit_from is None:
+        fit_from = -np.inf
+    if fit_to is None:
+        fit_to = np.inf
+
     y_fit = scan["Counts"]
     x_fit = scan[scan["scan_motor"]]
 
+    # apply fitting range
+    fit_ind = (fit_from <= x_fit) & (x_fit <= fit_to)
+    y_fit = y_fit[fit_ind]
+    x_fit = x_fit[fit_ind]
+
     model = None
     for model_index, (model_name, model_param) in enumerate(model_dict.items()):
         model_name, _ = model_name.split("-")