diff --git a/cereal/log.capnp b/cereal/log.capnp
index 9ab51e0b77..102118c3b6 100644
--- a/cereal/log.capnp
+++ b/cereal/log.capnp
@@ -2291,6 +2291,7 @@ struct LiveDelayData {
   lateralDelayEstimate @3 :Float32;
   lateralDelayEstimateStd @5 :Float32;
   points @4 :List(Float32);
+  calPerc @6 :Int8;
 
   enum Status {
     unestimated @0;
diff --git a/selfdrive/locationd/lagd.py b/selfdrive/locationd/lagd.py
index e070c16b1c..e6767db473 100755
--- a/selfdrive/locationd/lagd.py
+++ b/selfdrive/locationd/lagd.py
@@ -229,6 +229,8 @@ class LateralLagEstimator:
       liveDelay.lateralDelayEstimateStd = 0.0
 
     liveDelay.validBlocks = self.block_avg.valid_blocks
+    liveDelay.calPerc = min(100 * (self.block_avg.valid_blocks * self.block_size + self.block_avg.idx) //
+                            (self.min_valid_block_count * self.block_size), 100)
     if debug:
       liveDelay.points = self.block_avg.values.flatten().tolist()
 
diff --git a/selfdrive/locationd/test/test_lagd.py b/selfdrive/locationd/test/test_lagd.py
index a7f9c75ab4..8fb829edd8 100644
--- a/selfdrive/locationd/test/test_lagd.py
+++ b/selfdrive/locationd/test/test_lagd.py
@@ -94,6 +94,7 @@ class TestLagd:
     assert np.allclose(msg.liveDelay.lateralDelay, estimator.initial_lag)
     assert np.allclose(msg.liveDelay.lateralDelayEstimate, estimator.initial_lag)
     assert msg.liveDelay.validBlocks == 0
+    assert msg.liveDelay.calPerc == 0
 
   def test_estimator_basics(self, subtests):
     for lag_frames in range(5):
@@ -107,6 +108,7 @@ class TestLagd:
         assert np.allclose(msg.liveDelay.lateralDelayEstimate, lag_frames * DT, atol=0.01)
         assert np.allclose(msg.liveDelay.lateralDelayEstimateStd, 0.0, atol=0.01)
         assert msg.liveDelay.validBlocks == BLOCK_NUM_NEEDED
+        assert msg.liveDelay.calPerc == 100
 
   def test_disabled_estimator(self):
     mocked_CP = car.CarParams(steerActuatorDelay=0.8)
@@ -119,6 +121,7 @@ class TestLagd:
     assert np.allclose(msg.liveDelay.lateralDelayEstimate, lag_frames * DT, atol=0.01)
     assert np.allclose(msg.liveDelay.lateralDelayEstimateStd, 0.0, atol=0.01)
     assert msg.liveDelay.validBlocks == BLOCK_NUM_NEEDED
+    assert msg.liveDelay.calPerc == 100
 
   def test_estimator_masking(self):
     mocked_CP, lag_frames = car.CarParams(steerActuatorDelay=0.8), random.randint(1, 19)
@@ -127,6 +130,7 @@ class TestLagd:
     msg = estimator.get_msg(True)
     assert np.allclose(msg.liveDelay.lateralDelayEstimate, lag_frames * DT, atol=0.01)
     assert np.allclose(msg.liveDelay.lateralDelayEstimateStd, 0.0, atol=0.01)
+    assert msg.liveDelay.calPerc == 100
 
   @pytest.mark.skipif(PC, reason="only on device")
   @pytest.mark.timeout(60)