diff --git a/src/evdev-tablet.c b/src/evdev-tablet.c
index 395e5a0f..940a1e06 100644
--- a/src/evdev-tablet.c
+++ b/src/evdev-tablet.c
@@ -386,22 +386,23 @@ tablet_handle_xy(struct tablet_dispatch *tablet,
 }
 
 static inline struct normalized_coords
-tablet_process_delta(struct tablet_dispatch *tablet,
-		     const struct evdev_device *device,
-		     const struct device_coords *delta,
-		     uint64_t time)
+tool_process_delta(struct libinput_tablet_tool *tool,
+		   const struct evdev_device *device,
+		   const struct device_coords *delta,
+		   uint64_t time)
 {
 	struct normalized_coords accel;
 
-	/* The tablet accel code uses mm as input */
-	accel.x = 1.0 * delta->x/device->abs.absinfo_x->resolution;
-	accel.y = 1.0 * delta->y/device->abs.absinfo_y->resolution;
+	accel.x = 1.0 * delta->x;
+	accel.y = 1.0 * delta->y;
 
 	if (normalized_is_zero(accel))
 		return accel;
 
 	return filter_dispatch(device->pointer.filter,
-			       &accel, tablet, time);
+			       &accel,
+			       tool,
+			       time);
 }
 
 static inline double
@@ -548,7 +549,7 @@ tablet_check_notify_axes(struct tablet_dispatch *tablet,
 	axes.distance = tablet_handle_distance(tablet, device);
 	axes.slider = tablet_handle_slider(tablet, device);
 	axes.tilt = tablet_handle_tilt(tablet, device);
-	axes.delta = tablet_process_delta(tablet, device, &delta, time);
+	axes.delta = tool_process_delta(tool, device, &delta, time);
 
 	/* We must check ROTATION_Z after TILT_X/Y so that the tilt axes are
 	 * already normalized and set if we have the mouse/lens tool */
diff --git a/src/filter.c b/src/filter.c
index cf8996dd..0bb066c9 100644
--- a/src/filter.c
+++ b/src/filter.c
@@ -168,6 +168,8 @@ struct tablet_accelerator_flat {
 
 	double factor;
 	int xres, yres;
+	double xres_scale, /* 1000dpi : tablet res */
+	       yres_scale; /* 1000dpi : tablet res */
 };
 
 static void
@@ -972,17 +974,39 @@ create_pointer_accelerator_filter_flat(int dpi)
 	return &filter->base;
 }
 
-/* The tablet accel code uses mm as input */
-static struct normalized_coords
-tablet_accelerator_filter_flat(struct motion_filter *filter,
-			       const struct normalized_coords *mm,
-			       void *data, uint64_t time)
+static inline struct normalized_coords
+tablet_accelerator_filter_flat_mouse(struct tablet_accelerator_flat *filter,
+				     const struct normalized_coords *units)
 {
-	struct tablet_accelerator_flat *accel_filter =
-		(struct tablet_accelerator_flat *)filter;
 	struct normalized_coords accelerated;
 
-	/* Tablet input is in mm, output is supposed to be in logical
+	/*
+	   The input for and output of accel methods is usually a delta in
+	   1000dpi equivalents. Tablets are high res (Intuos 4 is 5080 dpi)
+	   and unmodified deltas are way too high. Slow it down to the
+	   equivalent of a 1000dpi mouse. The ratio of that is:
+		ratio = 1000/(resolution_per_mm * 25.4)
+
+	   i.e. on the Intuos4 it's a ratio of ~1/5.
+
+	 */
+
+	accelerated.x = units->x * filter->xres_scale;
+	accelerated.y = units->y * filter->yres_scale;
+
+	accelerated.x *= filter->factor;
+	accelerated.y *= filter->factor;
+
+	return accelerated;
+}
+
+static struct normalized_coords
+tablet_accelerator_filter_flat_pen(struct tablet_accelerator_flat *filter,
+				   const struct normalized_coords *units)
+{
+	struct normalized_coords accelerated;
+
+	/* Tablet input is in device units, output is supposed to be in logical
 	 * pixels roughly equivalent to a mouse/touchpad.
 	 *
 	 * This is a magical constant found by trial and error. On a 96dpi
@@ -990,12 +1014,43 @@ tablet_accelerator_filter_flat(struct motion_filter *filter,
 	 * is almost identical to the tablet mapped to screen in absolute
 	 * mode. Tested on a Intuos5, other tablets may vary.
 	 */
-	const double DPI_CONVERSION = 96.0/25.4 * 2.5; /* unitless factor */
+       const double DPI_CONVERSION = 96.0/25.4 * 2.5; /* unitless factor */
+       struct normalized_coords mm;
 
-	accelerated.x = mm->x * accel_filter->factor * DPI_CONVERSION;
-	accelerated.y = mm->y * accel_filter->factor * DPI_CONVERSION;
+       mm.x = 1.0 * units->x/filter->xres;
+       mm.y = 1.0 * units->y/filter->yres;
+       accelerated.x = mm.x * filter->factor * DPI_CONVERSION;
+       accelerated.y = mm.y * filter->factor * DPI_CONVERSION;
 
-	return accelerated;
+       return accelerated;
+}
+
+static struct normalized_coords
+tablet_accelerator_filter_flat(struct motion_filter *filter,
+			       const struct normalized_coords *units,
+			       void *data, uint64_t time)
+{
+	struct tablet_accelerator_flat *accel_filter =
+		(struct tablet_accelerator_flat *)filter;
+	struct libinput_tablet_tool *tool = (struct libinput_tablet_tool*)data;
+	enum libinput_tablet_tool_type type;
+	struct normalized_coords accel;
+
+	type = libinput_tablet_tool_get_type(tool);
+
+	switch (type) {
+	case LIBINPUT_TABLET_TOOL_TYPE_MOUSE:
+	case LIBINPUT_TABLET_TOOL_TYPE_LENS:
+		accel = tablet_accelerator_filter_flat_mouse(accel_filter,
+							     units);
+		break;
+	default:
+		accel = tablet_accelerator_filter_flat_pen(accel_filter,
+							   units);
+		break;
+	}
+
+	return accel;
 }
 
 static bool
@@ -1039,8 +1094,11 @@ create_tablet_filter_flat(int xres, int yres)
 	if (filter == NULL)
 		return NULL;
 
+	filter->factor = 1.0;
 	filter->xres = xres;
 	filter->yres = yres;
+	filter->xres_scale = DEFAULT_MOUSE_DPI/(25.4 * xres);
+	filter->yres_scale = DEFAULT_MOUSE_DPI/(25.4 * yres);
 
 	return filter;
 }
diff --git a/tools/Makefile.am b/tools/Makefile.am
index 8f72db99..5fe169cd 100644
--- a/tools/Makefile.am
+++ b/tools/Makefile.am
@@ -18,7 +18,7 @@ event_debug_LDFLAGS = -no-install
 event_debug_CFLAGS = $(LIBUDEV_CFLAGS) $(LIBEVDEV_CFLAGS)
 
 ptraccel_debug_SOURCES = ptraccel-debug.c
-ptraccel_debug_LDADD = ../src/libfilter.la
+ptraccel_debug_LDADD = ../src/libfilter.la ../src/libinput.la
 ptraccel_debug_LDFLAGS = -no-install
 
 libinput_list_devices_SOURCES = libinput-list-devices.c