diff --git a/README.md b/README.md
index 707d90e1d..3d1f3be55 100644
--- a/README.md
+++ b/README.md
@@ -132,6 +132,7 @@ InlineEditor.defaultConfig = {
 		engine: 'mathjax', // or katex or function. E.g. (equation, element, display) => { ... }
 		lazyLoad: undefined, // async () => { ... }, called once before rendering first equation if engine doesn't exist. After resolving promise, plugin renders equations.
 		outputType: 'script', // or span
+		className: 'math-tex', // class name to use with span output type, change e.g. MathJax processClass (v2) / processHtmlClass (v3) is set
 		forceOutputType: false, // forces output to use outputType
 		enablePreview: true, // Enable preview view
 		previewClassName: [], // Class names to add to previews
diff --git a/src/mathediting.js b/src/mathediting.js
index 1268e3c60..5a4a1973a 100644
--- a/src/mathediting.js
+++ b/src/mathediting.js
@@ -26,6 +26,7 @@ export default class MathEditing extends Plugin {
 		editor.config.define( 'math', {
 			engine: 'mathjax',
 			outputType: 'script',
+			className: 'math-tex',
 			forceOutputType: false,
 			enablePreview: true,
 			previewClassName: [],
@@ -95,7 +96,7 @@ export default class MathEditing extends Plugin {
 			.elementToElement( {
 				view: {
 					name: 'span',
-					classes: [ 'math-tex' ]
+					classes: [ mathConfig.className ]
 				},
 				model: ( viewElement, { writer } ) => {
 					const equation = viewElement.getChild( 0 ).data.trim();
@@ -185,7 +186,7 @@ export default class MathEditing extends Plugin {
 
 			if ( type === 'span' ) {
 				const mathtexView = writer.createContainerElement( 'span', {
-					class: 'math-tex'
+					class: mathConfig.className
 				} );
 
 				if ( display ) {