diff --git a/.changeset/eighty-rice-happen.md b/.changeset/eighty-rice-happen.md
new file mode 100644
index 0000000000..8a1b450af7
--- /dev/null
+++ b/.changeset/eighty-rice-happen.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-techdocs': patch
+---
+
+Match text size of admonitions to main content text size.
diff --git a/plugins/techdocs/src/reader/components/Reader.tsx b/plugins/techdocs/src/reader/components/Reader.tsx
index 61617ba9ec..c12b17b486 100644
--- a/plugins/techdocs/src/reader/components/Reader.tsx
+++ b/plugins/techdocs/src/reader/components/Reader.tsx
@@ -270,7 +270,7 @@ export const useTechDocsReaderDom = (entityRef: EntityName): Element | null => {
           }
           .md-typeset table:not([class]) th { font-weight: bold; }
           .md-typeset .admonition, .md-typeset details {
-            font-size: 1rem;
+            font-size: inherit;
           }
           
           /* style the checkmarks of the task list */