diff --git a/openpilot/selfdrive/ui/mici/onroad/augmented_road_view.py b/openpilot/selfdrive/ui/mici/onroad/augmented_road_view.py
index ffd7d94b2e..919154d6fb 100644
--- a/openpilot/selfdrive/ui/mici/onroad/augmented_road_view.py
+++ b/openpilot/selfdrive/ui/mici/onroad/augmented_road_view.py
@@ -22,6 +22,7 @@ from openpilot.common.transformations.orientation import rot_from_euler
 from enum import IntEnum
 
 if gui_app.sunnypilot_ui():
+  from openpilot.selfdrive.ui.sunnypilot.mici.onroad.accel_boost_indicator import AccelBoostIndicator
   from openpilot.selfdrive.ui.sunnypilot.mici.onroad.hud_renderer import HudRendererSP as HudRenderer
   from openpilot.selfdrive.ui.sunnypilot.ui_state import OnroadTimerStatus
 
@@ -181,6 +182,7 @@ class AugmentedRoadView(CameraView):
     self._alert_renderer = AlertRenderer()
     self._driver_state_renderer = DriverStateRenderer()
     self._confidence_ball = ConfidenceBall()
+    self._accel_boost_indicator = AccelBoostIndicator() if gui_app.sunnypilot_ui() else None
     self._offroad_label = UnifiedLabel("start the car to\nuse sunnypilot", 54, FontWeight.DISPLAY,
                                        text_color=rl.Color(255, 255, 255, int(255 * 0.9)),
                                        alignment=TextAlignment.CENTER,
@@ -274,6 +276,11 @@ class AugmentedRoadView(CameraView):
     # Use self._content_rect for positioning within camera bounds
     if show_navigation:
       self._navigation.render(rl.Rectangle(self._content_rect.x + self._content_rect.width, self.rect.y, PANEL_WIDTH, self.rect.height))
+    elif self._accel_boost_indicator is not None:
+      # The boost bar owns the side panel while the feature is on; the ball only shows otherwise
+      self._accel_boost_indicator.render(self.rect)
+      if not self._accel_boost_indicator.panel_in_use:
+        self._confidence_ball.render(self.rect)
     else:
       self._confidence_ball.render(self.rect)
 
diff --git a/openpilot/selfdrive/ui/sunnypilot/mici/onroad/accel_boost_indicator.py b/openpilot/selfdrive/ui/sunnypilot/mici/onroad/accel_boost_indicator.py
new file mode 100644
index 0000000000..f0720cc5ba
--- /dev/null
+++ b/openpilot/selfdrive/ui/sunnypilot/mici/onroad/accel_boost_indicator.py
@@ -0,0 +1,146 @@
+"""
+Copyright (c) 2021-, Haibin Wen, sunnypilot, and a number of other contributors.
+
+This file is part of sunnypilot and is licensed under the MIT License.
+See the LICENSE.md file in the root directory for more details.
+"""
+import pyray as rl
+
+from openpilot.common.filter_simple import FirstOrderFilter
+from openpilot.selfdrive.ui.mici.onroad import SIDE_PANEL_WIDTH
+from openpilot.selfdrive.ui.ui_state import ui_state
+from openpilot.sunnypilot.selfdrive.controls.lib.accel_boost import ACCEL_BOOST_MAX
+from openpilot.system.ui.lib.application import gui_app
+from openpilot.system.ui.widgets import Widget
+
+BAR_WIDTH = 26
+BAR_RADIUS = 0.5
+TRACK_TOP_RATIO = 0.08
+TRACK_BOTTOM_RATIO = 0.92
+# Fades to white only near the profile cap, like the stock torque bar fading toward orange at high torque
+CAP_BLEND_START = 0.70
+MAX_BOOST_BLEND = 0.55
+
+COLOR_TRACK = rl.Color(255, 255, 255, 32)
+COLOR_TRACK_EDGE = rl.Color(255, 255, 255, 70)
+COLOR_HIGHLIGHT = rl.Color(255, 255, 255, 45)
+
+AGGRESSIVE_COLOR = rl.Color(255, 80, 60, 255)
+STANDARD_COLOR = rl.Color(0, 230, 120, 255)
+RELAXED_COLOR = rl.Color(70, 150, 255, 255)
+
+# The personality enum is ordered aggressive, standard, relaxed, matching ACCEL_BOOST_MAX
+PROFILE_STYLES = {
+  0: (AGGRESSIVE_COLOR, ACCEL_BOOST_MAX[0]),
+  1: (STANDARD_COLOR, ACCEL_BOOST_MAX[1]),
+  2: (RELAXED_COLOR, ACCEL_BOOST_MAX[2]),
+}
+
+FADE_THRESHOLD = 0.01
+
+
+def get_boost_style(personality) -> tuple[rl.Color, float]:
+  """Color and full-scale boost for the active personality."""
+  raw = getattr(personality, "raw", personality)
+  return PROFILE_STYLES.get(int(raw), PROFILE_STYLES[1])
+
+
+def get_boost_fraction(boost: float, max_boost: float) -> float:
+  """How much of the active profile's boost budget is in use, clamped to a full bar."""
+  if max_boost <= 0.0:
+    return 0.0
+  return min(max(boost / max_boost, 0.0), 1.0)
+
+
+def lighten(color: rl.Color, amount: float) -> rl.Color:
+  """Lerp towards white in RGB, so the hue stays put the way HSV blending would not."""
+  amount = min(max(amount, 0.0), 1.0)
+  return rl.Color(int(color.r + (255 - color.r) * amount),
+                  int(color.g + (255 - color.g) * amount),
+                  int(color.b + (255 - color.b) * amount), color.a)
+
+
+class AccelBoostIndicator(Widget):
+  def __init__(self):
+    super().__init__()
+    fps = max(gui_app.target_fps, 1)
+    self._boost_filter = FirstOrderFilter(0.0, 0.15, 1 / fps)
+    self._alpha_filter = FirstOrderFilter(0.0, 0.1, 1 / fps)
+    # Smoothly rescale the bar when the follow distance profile changes mid-drive
+    self._max_boost_filter = FirstOrderFilter(0.0, 0.25, 1 / fps)
+    self._profile_color, self._max_boost = PROFILE_STYLES[1]
+
+    self.panel_in_use = False
+
+  def _update_state(self):
+    sm = ui_state.sm
+    visible = (ui_state.has_longitudinal_control and sm.alive['selfdriveState'] and
+               sm.alive['longitudinalPlan'] and sm['selfdriveState'].enabled)
+    self._alpha_filter.update(1.0 if visible else 0.0)
+    self._boost_filter.update(float(sm['longitudinalPlan'].accelBoost) if visible else 0.0)
+
+    if sm.alive['selfdriveState']:
+      self._profile_color, self._max_boost = get_boost_style(sm['selfdriveState'].personality)
+    self._max_boost_filter.update(self._max_boost)
+
+    # The bar owns the panel while it is drawn; the confidence ball returns when it fades out
+    self.panel_in_use = self._alpha_filter.x > FADE_THRESHOLD
+
+  def _render(self, _):
+    alpha = self._alpha_filter.x
+    if alpha < FADE_THRESHOLD or self._max_boost <= 0.0:
+      return
+
+    panel_x = self.rect.x + self.rect.width - SIDE_PANEL_WIDTH
+    cx = panel_x + SIDE_PANEL_WIDTH / 2
+    bar_x = cx - BAR_WIDTH / 2
+    track_top = self.rect.y + self.rect.height * TRACK_TOP_RATIO
+    track_bottom = self.rect.y + self.rect.height * TRACK_BOTTOM_RATIO
+    track_h = max(1.0, track_bottom - track_top)
+    track_rect = rl.Rectangle(bar_x, track_top, BAR_WIDTH, track_h)
+
+    # soft well behind the track so the bar reads on the black side panel
+    rl.draw_rectangle_rounded(rl.Rectangle(bar_x - 3, track_top - 3, BAR_WIDTH + 6, track_h + 6), BAR_RADIUS, 12,
+                              rl.Color(0, 0, 0, int(80 * alpha)))
+
+    # track, light enough to read on the black side panel
+    rl.draw_rectangle_rounded(track_rect, BAR_RADIUS, 12,
+                              rl.Color(COLOR_TRACK.r, COLOR_TRACK.g, COLOR_TRACK.b, int(COLOR_TRACK.a * alpha)))
+    rl.draw_rectangle_rounded_lines_ex(track_rect, BAR_RADIUS, 12, 1,
+                                       rl.Color(COLOR_TRACK_EDGE.r, COLOR_TRACK_EDGE.g, COLOR_TRACK_EDGE.b,
+                                                int(COLOR_TRACK_EDGE.a * alpha)))
+
+    # Scale to the current profile's cap, so a maxed boost fills the bar and a profile change rescales it
+    boost = max(self._boost_filter.x, 0.0)
+    ratio = get_boost_fraction(boost, self._max_boost_filter.x)
+    fill_h = ratio * track_h
+    if fill_h <= 0.0:
+      return
+
+    cap_blend = max(0.0, (ratio - CAP_BLEND_START) / (1.0 - CAP_BLEND_START))
+    fill_color = lighten(self._profile_color, MAX_BOOST_BLEND * cap_blend)
+    tip_y = track_bottom - fill_h
+
+    # soft glow around the tip, like the confidence ball's gradient
+    tip_center_y = tip_y + min(fill_h, BAR_WIDTH) / 2
+    glow = rl.Color(fill_color.r, fill_color.g, fill_color.b, int(85 * alpha))
+    rl.draw_circle_gradient(rl.Vector2(cx, tip_center_y), int(BAR_WIDTH * 0.85), glow, rl.BLANK)
+
+    fill = rl.Color(fill_color.r, fill_color.g, fill_color.b, int(255 * alpha))
+    if fill_h < BAR_WIDTH:
+      # Keep the cap inside the track: a fixed radius would paint below the track near zero boost
+      radius = max(1, int(fill_h / 2))
+      rl.draw_circle(int(cx), int(track_bottom - radius), radius, fill)
+    else:
+      rl.draw_rectangle_rounded(rl.Rectangle(bar_x, tip_y, BAR_WIDTH, fill_h), BAR_RADIUS, 12, fill)
+
+      # subtle inner highlight gives the fill a rounded, glassy edge
+      if fill_h > 12:
+        highlight_rect = rl.Rectangle(bar_x + 4, tip_y + 5, 3, fill_h - 10)
+        rl.draw_rectangle_rounded(highlight_rect, 0.5, 8,
+                                  rl.Color(COLOR_HIGHLIGHT.r, COLOR_HIGHLIGHT.g, COLOR_HIGHLIGHT.b,
+                                           int(COLOR_HIGHLIGHT.a * alpha)))
+
+      # bright cap at the tip
+      rl.draw_circle(int(cx), int(tip_center_y), 2,
+                     rl.Color(255, 255, 255, int(150 * alpha)))
diff --git a/openpilot/selfdrive/ui/sunnypilot/mici/tests/test_accel_boost_indicator.py b/openpilot/selfdrive/ui/sunnypilot/mici/tests/test_accel_boost_indicator.py
new file mode 100644
index 0000000000..3040bf53d6
--- /dev/null
+++ b/openpilot/selfdrive/ui/sunnypilot/mici/tests/test_accel_boost_indicator.py
@@ -0,0 +1,52 @@
+"""
+Copyright (c) 2021-, Haibin Wen, sunnypilot, and a number of other contributors.
+
+This file is part of sunnypilot and is licensed under the MIT License.
+See the LICENSE.md file in the root directory for more details.
+"""
+from openpilot.cereal import log
+from openpilot.common.test import OpenpilotTestCase
+from openpilot.selfdrive.ui.sunnypilot.mici.onroad.accel_boost_indicator import (
+  get_boost_style, get_boost_fraction, lighten,
+  AGGRESSIVE_COLOR, RELAXED_COLOR, STANDARD_COLOR,
+)
+from openpilot.sunnypilot.selfdrive.controls.lib.accel_boost import ACCEL_BOOST_MAX
+
+
+class TestAccelBoostIndicator(OpenpilotTestCase):
+  def test_profile_styles_match_controller_caps(self):
+    for personality, color, max_boost in (
+        (log.LongitudinalPersonality.aggressive, AGGRESSIVE_COLOR, ACCEL_BOOST_MAX[0]),
+        (log.LongitudinalPersonality.standard, STANDARD_COLOR, ACCEL_BOOST_MAX[1]),
+        (log.LongitudinalPersonality.relaxed, RELAXED_COLOR, ACCEL_BOOST_MAX[2])):
+      style_color, style_max = get_boost_style(personality)
+      assert style_color == color
+      assert style_max == max_boost
+
+  def test_wire_personality_picks_the_right_profile(self):
+    msg = log.SelfdriveState.new_message()
+    msg.personality = log.LongitudinalPersonality.aggressive
+    color, max_boost = get_boost_style(msg.personality)
+    assert color == AGGRESSIVE_COLOR
+    assert max_boost == ACCEL_BOOST_MAX[0]
+
+  def test_bar_fills_at_the_active_profile_cap(self):
+    for cap in ACCEL_BOOST_MAX:
+      assert get_boost_fraction(0.0, cap) == 0.0
+      assert get_boost_fraction(cap * 0.5, cap) == 0.5
+      assert get_boost_fraction(cap, cap) == 1.0
+
+    # A boost beyond the current cap (e.g. after switching to a shorter profile) still fills the bar
+    assert get_boost_fraction(max(ACCEL_BOOST_MAX), min(ACCEL_BOOST_MAX)) == 1.0
+    assert get_boost_fraction(0.0, 0.0) == 0.0
+
+  def test_cap_lighten_keeps_the_profile_hue(self):
+    # An HSV blend towards white sweeps relaxed blue through pink, so the fill lightens in RGB instead
+    relaxed = lighten(RELAXED_COLOR, 0.45)
+    aggressive = lighten(AGGRESSIVE_COLOR, 0.45)
+    assert relaxed.b > relaxed.r
+    assert relaxed.b >= relaxed.g
+    assert aggressive.r > aggressive.b
+    # lighter in RGB means the dimmest channel came up towards white
+    assert relaxed.r > RELAXED_COLOR.r
+    assert aggressive.g > AGGRESSIVE_COLOR.g