diff --git a/poincare/src/zoom.cpp b/poincare/src/zoom.cpp
index 5a848d6f8..eabf47192 100644
--- a/poincare/src/zoom.cpp
+++ b/poincare/src/zoom.cpp
@@ -266,8 +266,9 @@ void Zoom::RangeWithRatioForDisplay(ValueAtAbscissa evaluation, float yxRatio, f
     RefinedYRangeForDisplay(evaluation, center - xRange, center + xRange, &yMinRange, &yMaxRange, context, auxiliary, sampleSize);
     float currentRatio = (yMaxRange - yMinRange) / (2 * xRange);
     float grade = std::fabs(std::log(currentRatio / yxRatio));
-    /* When in doubt, favor ranges between [-1, 1] and [-10, 10] */
-    grade += std::fabs(std::log(xRange / 10.f) * std::log(xRange)) * rangeMagnitudeWeight;
+    /* The weigth function favors the [-5, 5] range, which will expand into
+     * the [-10, 10] range */
+    grade += std::fabs(std::log(xRange / k_largeUnitMantissa)) * rangeMagnitudeWeight;
     if (std::fabs(std::log(currentRatio / yxRatio)) < maxMagnitudeDifference && grade < bestGrade) {
       bestGrade = grade;
       bestUnit = unit;
diff --git a/poincare/test/zoom.cpp b/poincare/test/zoom.cpp
index c5b157f2f..f8fde7759 100644
--- a/poincare/test/zoom.cpp
+++ b/poincare/test/zoom.cpp
@@ -143,7 +143,7 @@ void assert_orthonormal_range_is(const char * definition, float targetXMin, floa
 
 QUIZ_CASE(poincare_zoom_range_with_ratio) {
   assert_orthonormal_range_is("1", NAN, NAN, NAN, NAN);
-  assert_orthonormal_range_is("x", -5, 5, -2.21179414, 2.21179414);
+  assert_orthonormal_range_is("x", -20, 20, -8.84717655, 8.84717655);
   assert_orthonormal_range_is("x^2", -2, 2, -0.172234654, 1.59720063);
   assert_orthonormal_range_is("x^3", -5, 5, -2.21179414, 2.21179414);
   assert_orthonormal_range_is("ℯ^x", -5, 5, -0.852653265, 3.57093501);