diff --git a/docs/Config_Changes.md b/docs/Config_Changes.md
index 14c3b12b..43e11b21 100644
--- a/docs/Config_Changes.md
+++ b/docs/Config_Changes.md
@@ -8,6 +8,9 @@ All dates in this document are approximate.
 
 ## Changes
 
+20230519: `SHAPER_CALIBRATE` command immediately applies input shaper parameters
+if `[input_shaper]` was enabled already.
+
 20230407: The `stalled_bytes` counter in the log and in the
 `printer.mcu.last_stats` field has been renamed to `upcoming_bytes`.
 
diff --git a/docs/G-Codes.md b/docs/G-Codes.md
index fe24a580..a6d056bf 100644
--- a/docs/G-Codes.md
+++ b/docs/G-Codes.md
@@ -1032,7 +1032,9 @@ frequency responses and the different input shapers values are written
 to a CSV file(s) `/tmp/calibration_data_<axis>_<name>.csv`. Unless
 specified, NAME defaults to the current time in "YYYYMMDD_HHMMSS"
 format. Note that the suggested input shaper parameters can be
-persisted in the config by issuing `SAVE_CONFIG` command.
+persisted in the config by issuing `SAVE_CONFIG` command, and if
+`[input_shaper]` was already enabled previously, these parameters
+take effect immediately.
 
 ### [respond]
 
diff --git a/klippy/extras/resonance_tester.py b/klippy/extras/resonance_tester.py
index 819d8155..d5f43b77 100644
--- a/klippy/extras/resonance_tester.py
+++ b/klippy/extras/resonance_tester.py
@@ -287,6 +287,8 @@ class ResonanceTester:
         if not self.is_valid_name_suffix(name_suffix):
             raise gcmd.error("Invalid NAME parameter")
 
+        input_shaper = self.printer.lookup_object('input_shaper', None)
+
         # Setup shaper calibration
         helper = shaper_calibrate.ShaperCalibrate(self.printer)
 
@@ -306,6 +308,9 @@ class ResonanceTester:
                     "Recommended shaper_type_%s = %s, shaper_freq_%s = %.1f Hz"
                     % (axis_name, best_shaper.name,
                        axis_name, best_shaper.freq))
+            if input_shaper is not None:
+                helper.apply_params(input_shaper, axis_name,
+                                    best_shaper.name, best_shaper.freq)
             helper.save_params(configfile, axis_name,
                                best_shaper.name, best_shaper.freq)
             csv_name = self.save_calibration_data(
diff --git a/klippy/extras/shaper_calibrate.py b/klippy/extras/shaper_calibrate.py
index 4ac58970..af77845c 100644
--- a/klippy/extras/shaper_calibrate.py
+++ b/klippy/extras/shaper_calibrate.py
@@ -334,6 +334,18 @@ class ShaperCalibrate:
             configfile.set('input_shaper', 'shaper_freq_'+axis,
                            '%.1f' % (shaper_freq,))
 
+    def apply_params(self, input_shaper, axis, shaper_name, shaper_freq):
+        if axis == 'xy':
+            self.apply_params(input_shaper, 'x', shaper_name, shaper_freq)
+            self.apply_params(input_shaper, 'y', shaper_name, shaper_freq)
+            return
+        gcode = self.printer.lookup_object("gcode")
+        axis = axis.upper()
+        input_shaper.cmd_SET_INPUT_SHAPER(gcode.create_gcode_command(
+                "SET_INPUT_SHAPER", "SET_INPUT_SHAPER", {
+                    "SHAPER_TYPE_" + axis: shaper_name,
+                    "SHAPER_FREQ_" + axis: shaper_freq}))
+
     def save_calibration_data(self, output, calibration_data, shapers=None):
         try:
             with open(output, "w") as csvfile: