diff --git a/library/src/main/java/ru/noties/markwon/spans/SpannableTheme.java b/library/src/main/java/ru/noties/markwon/spans/SpannableTheme.java
index 9eb36b3a..06462f67 100644
--- a/library/src/main/java/ru/noties/markwon/spans/SpannableTheme.java
+++ b/library/src/main/java/ru/noties/markwon/spans/SpannableTheme.java
@@ -176,6 +176,11 @@ public class SpannableTheme {
     // by default, whatever typeface is set on the TextView
     protected final Typeface headingTypeface;
 
+    // by default, we use standard multipliers from the HTML spec (see HEADING_SIZES for values).
+    // this library supports 6 heading sizes, so make sure the array you pass here has 6 elements.
+    // note also that these values are in PIXELS, so you'll need to convert from SP first.
+    protected final float[] headingTextSizes;
+
     // by default `SCRIPT_DEF_TEXT_SIZE_RATIO`
     protected final float scriptTextSizeRatio;
 
@@ -218,6 +223,7 @@ public class SpannableTheme {
         this.headingBreakHeight = builder.headingBreakHeight;
         this.headingBreakColor = builder.headingBreakColor;
         this.headingTypeface = builder.headingTypeface;
+        this.headingTextSizes = builder.headingTextSizes;
         this.scriptTextSizeRatio = builder.scriptTextSizeRatio;
         this.thematicBreakColor = builder.thematicBreakColor;
         this.thematicBreakHeight = builder.thematicBreakHeight;
@@ -377,7 +383,11 @@ public class SpannableTheme {
         } else {
             paint.setTypeface(headingTypeface);
         }
-        paint.setTextSize(paint.getTextSize() * HEADING_SIZES[level - 1]);
+        if (headingTextSizes != null && headingTextSizes.length >= level) {
+            paint.setTextSize(headingTextSizes[level - 1]);
+        } else {
+            paint.setTextSize(paint.getTextSize() * HEADING_SIZES[level - 1]);
+        }
     }
 
     public void applyHeadingBreakStyle(@NonNull Paint paint) {
@@ -500,6 +510,7 @@ public class SpannableTheme {
         private int headingBreakHeight = -1;
         private int headingBreakColor;
         private Typeface headingTypeface;
+        private float[] headingTextSizes;
         private float scriptTextSizeRatio;
         private int thematicBreakColor;
         private int thematicBreakHeight = -1;
@@ -530,6 +541,7 @@ public class SpannableTheme {
             this.headingBreakHeight = theme.headingBreakHeight;
             this.headingBreakColor = theme.headingBreakColor;
             this.headingTypeface = theme.headingTypeface;
+            this.headingTextSizes = theme.headingTextSizes;
             this.scriptTextSizeRatio = theme.scriptTextSizeRatio;
             this.thematicBreakColor = theme.thematicBreakColor;
             this.thematicBreakHeight = theme.thematicBreakHeight;
@@ -650,6 +662,12 @@ public class SpannableTheme {
             return this;
         }
 
+        @NonNull
+        public Builder headingTextSizes(float[] headingTextSizes) {
+            this.headingTextSizes = headingTextSizes;
+            return this;
+        }
+
         @NonNull
         public Builder scriptTextSizeRatio(@FloatRange(from = .0F, to = Float.MAX_VALUE) float scriptTextSizeRatio) {
             this.scriptTextSizeRatio = scriptTextSizeRatio;