diff --git a/README.md b/README.md
index 4eff5d9..4882404 100644
--- a/README.md
+++ b/README.md
@@ -174,6 +174,7 @@ settings = {
     maxFontSize: 80,
     reProcess: true, // if true, textFit will re-process already-fit nodes. Set to 'false' for better performance
     widthOnly: false, // if true, textFit will fit text to element width, regardless of text height
+    heightOnly: false, // if true, textFit will fit text to element height, regardless of text width
     alignVertWithFlexbox: false, // if true, textFit will use flexbox for vertical alignment
 };
 ```
diff --git a/index.d.ts b/index.d.ts
index 94fc528..35ce297 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -11,6 +11,7 @@ declare module "textfit" {
     maxFontSize?: number;
     reProcess?: boolean;
     widthOnly?: boolean;
+    heightOnly?: boolean;
     alignVertWithFlexbox?: boolean;
   }
 
diff --git a/textFit.js b/textFit.js
index 1bd0cf9..9600373 100644
--- a/textFit.js
+++ b/textFit.js
@@ -40,6 +40,7 @@
     maxFontSize: 80,
     reProcess: true, // if true, textFit will re-process already-fit nodes. Set to 'false' for better performance
     widthOnly: false, // if true, textFit will fit text to element width, regardless of text height
+    heightOnly: false, // if true, textFit will fit text to element height, regardless of text width
     alignVertWithFlexbox: false, // if true, textFit will use flexbox for vertical alignment
   };
 
@@ -99,13 +100,16 @@
     originalHeight = innerHeight(el);
 
     // Don't process if we can't find box dimensions
-    if (!originalWidth || (!settings.widthOnly && !originalHeight)) {
-      if(!settings.widthOnly)
+    if ((!settings.heightOnly && !originalWidth) || (!settings.widthOnly && !originalHeight)) {
+      if(!settings.widthOnly && !settings.heightOnly)
         throw new Error('Set a static height and width on the target element ' + el.outerHTML +
           ' before using textFit!');
-      else
+      else if (!settings.heightOnly)
         throw new Error('Set a static width on the target element ' + el.outerHTML +
           ' before using textFit!');
+      else if (!settings.widthOnly)
+        throw new Error('Set a static height on the target element ' + el.outerHTML +
+          ' before using textFit!');
     }
 
     // Add textFitted span inside this container.
@@ -158,8 +162,8 @@
       innerSpan.style.fontSize = mid + 'px';
       var innerSpanBoundingClientRect = innerSpan.getBoundingClientRect();
       if (
-        innerSpanBoundingClientRect.width <= originalWidth 
-        && (settings.widthOnly || innerSpanBoundingClientRect.height <= originalHeight)
+           (settings.heightOnly || innerSpanBoundingClientRect.width  <= originalWidth)
+        && (settings.widthOnly  || innerSpanBoundingClientRect.height <= originalHeight)
       ) {
         size = mid;
         low = mid + 1;
diff --git a/textFit.min.js b/textFit.min.js
index d2af16d..f280263 100644
--- a/textFit.min.js
+++ b/textFit.min.js
@@ -1 +1 @@
-(function(root,factory){"use strict";if(typeof define==="function"&&define.amd){define([],factory)}else if(typeof exports==="object"){module.exports=factory()}else{root.textFit=factory()}})(typeof global==="object"?global:this,function(){"use strict";var defaultSettings={alignVert:false,alignHoriz:false,multiLine:false,detectMultiLine:true,minFontSize:6,maxFontSize:80,reProcess:true,widthOnly:false,alignVertWithFlexbox:false};return function textFit(els,options){if(!options)options={};var settings={};for(var key in defaultSettings){if(options.hasOwnProperty(key)){settings[key]=options[key]}else{settings[key]=defaultSettings[key]}}if(typeof els.toArray==="function"){els=els.toArray()}var elType=Object.prototype.toString.call(els);if(elType!=="[object Array]"&&elType!=="[object NodeList]"&&elType!=="[object HTMLCollection]"){els=[els]}for(var i=0;i<els.length;i++){processItem(els[i],settings)}};function processItem(el,settings){if(!isElement(el)||!settings.reProcess&&el.getAttribute("textFitted")){return false}if(!settings.reProcess){el.setAttribute("textFitted",1)}var innerSpan,originalHeight,originalHTML,originalWidth;var low,mid,high;originalHTML=el.innerHTML;originalWidth=innerWidth(el);originalHeight=innerHeight(el);if(!originalWidth||!settings.widthOnly&&!originalHeight){if(!settings.widthOnly)throw new Error("Set a static height and width on the target element "+el.outerHTML+" before using textFit!");else throw new Error("Set a static width on the target element "+el.outerHTML+" before using textFit!")}if(originalHTML.indexOf("textFitted")===-1){innerSpan=document.createElement("span");innerSpan.className="textFitted";innerSpan.style["display"]="inline-block";innerSpan.innerHTML=originalHTML;el.innerHTML="";el.appendChild(innerSpan)}else{innerSpan=el.querySelector("span.textFitted");if(hasClass(innerSpan,"textFitAlignVert")){innerSpan.className=innerSpan.className.replace("textFitAlignVert","");innerSpan.style["height"]="";el.className.replace("textFitAlignVertFlex","")}}if(settings.alignHoriz){el.style["text-align"]="center";innerSpan.style["text-align"]="center"}var multiLine=settings.multiLine;if(settings.detectMultiLine&&!multiLine&&innerSpan.scrollHeight>=parseInt(window.getComputedStyle(innerSpan)["font-size"],10)*2){multiLine=true}if(!multiLine){el.style["white-space"]="nowrap"}low=settings.minFontSize;high=settings.maxFontSize;var size=low;while(low<=high){mid=high+low>>1;innerSpan.style.fontSize=mid+"px";if(innerSpan.scrollWidth<=originalWidth&&(settings.widthOnly||innerSpan.scrollHeight<=originalHeight)){size=mid;low=mid+1}else{high=mid-1}}if(innerSpan.style.fontSize!=size+"px")innerSpan.style.fontSize=size+"px";if(settings.alignVert){addStyleSheet();var height=innerSpan.scrollHeight;if(window.getComputedStyle(el)["position"]==="static"){el.style["position"]="relative"}if(!hasClass(innerSpan,"textFitAlignVert")){innerSpan.className=innerSpan.className+" textFitAlignVert"}innerSpan.style["height"]=height+"px";if(settings.alignVertWithFlexbox&&!hasClass(el,"textFitAlignVertFlex")){el.className=el.className+" textFitAlignVertFlex"}}}function innerHeight(el){var style=window.getComputedStyle(el,null);return el.clientHeight-parseInt(style.getPropertyValue("padding-top"),10)-parseInt(style.getPropertyValue("padding-bottom"),10)}function innerWidth(el){var style=window.getComputedStyle(el,null);return el.clientWidth-parseInt(style.getPropertyValue("padding-left"),10)-parseInt(style.getPropertyValue("padding-right"),10)}function isElement(o){return typeof HTMLElement==="object"?o instanceof HTMLElement:o&&typeof o==="object"&&o!==null&&o.nodeType===1&&typeof o.nodeName==="string"}function hasClass(element,cls){return(" "+element.className+" ").indexOf(" "+cls+" ")>-1}function addStyleSheet(){if(document.getElementById("textFitStyleSheet"))return;var style=[".textFitAlignVert{","position: absolute;","top: 0; right: 0; bottom: 0; left: 0;","margin: auto;","display: flex;","justify-content: center;","flex-direction: column;","}",".textFitAlignVertFlex{","display: flex;","}",".textFitAlignVertFlex .textFitAlignVert{","position: static;","}"].join("");var css=document.createElement("style");css.type="text/css";css.id="textFitStyleSheet";css.innerHTML=style;document.body.appendChild(css)}});
+(function(root,factory){"use strict";if(typeof define==="function"&&define.amd){define([],factory)}else if(typeof exports==="object"){module.exports=factory()}else{root.textFit=factory()}})(typeof global==="object"?global:this,function(){"use strict";var defaultSettings={alignVert:false,alignHoriz:false,multiLine:false,detectMultiLine:true,minFontSize:6,maxFontSize:80,reProcess:true,widthOnly:false,heightOnly:false,alignVertWithFlexbox:false};return function textFit(els,options){if(!options)options={};var settings={};for(var key in defaultSettings){if(options.hasOwnProperty(key)){settings[key]=options[key]}else{settings[key]=defaultSettings[key]}}if(typeof els.toArray==="function"){els=els.toArray()}var elType=Object.prototype.toString.call(els);if(elType!=="[object Array]"&&elType!=="[object NodeList]"&&elType!=="[object HTMLCollection]"){els=[els]}for(var i=0;i<els.length;i++){processItem(els[i],settings)}};function processItem(el,settings){if(!isElement(el)||!settings.reProcess&&el.getAttribute("textFitted")){return false}if(!settings.reProcess){el.setAttribute("textFitted",1)}var innerSpan,originalHeight,originalHTML,originalWidth;var low,mid,high;originalHTML=el.innerHTML;originalWidth=innerWidth(el);originalHeight=innerHeight(el);if(!settings.heightOnly&&!originalWidth||!settings.widthOnly&&!originalHeight){if(!settings.widthOnly&&!settings.heightOnly)throw new Error("Set a static height and width on the target element "+el.outerHTML+" before using textFit!");else if(!settings.heightOnly)throw new Error("Set a static width on the target element "+el.outerHTML+" before using textFit!");else if(!settings.widthOnly)throw new Error("Set a static height on the target element "+el.outerHTML+" before using textFit!")}if(originalHTML.indexOf("textFitted")===-1){innerSpan=document.createElement("span");innerSpan.className="textFitted";innerSpan.style["display"]="inline-block";innerSpan.innerHTML=originalHTML;el.innerHTML="";el.appendChild(innerSpan)}else{innerSpan=el.querySelector("span.textFitted");if(hasClass(innerSpan,"textFitAlignVert")){innerSpan.className=innerSpan.className.replace("textFitAlignVert","");innerSpan.style["height"]="";el.className.replace("textFitAlignVertFlex","")}}if(settings.alignHoriz){el.style["text-align"]="center";innerSpan.style["text-align"]="center"}var multiLine=settings.multiLine;if(settings.detectMultiLine&&!multiLine&&innerSpan.getBoundingClientRect().height>=parseInt(window.getComputedStyle(innerSpan)["font-size"],10)*2){multiLine=true}if(!multiLine){el.style["white-space"]="nowrap"}low=settings.minFontSize;high=settings.maxFontSize;var size=low;while(low<=high){mid=high+low>>1;innerSpan.style.fontSize=mid+"px";var innerSpanBoundingClientRect=innerSpan.getBoundingClientRect();if((settings.heightOnly||innerSpanBoundingClientRect.width<=originalWidth)&&(settings.widthOnly||innerSpanBoundingClientRect.height<=originalHeight)){size=mid;low=mid+1}else{high=mid-1}}if(innerSpan.style.fontSize!=size+"px")innerSpan.style.fontSize=size+"px";if(settings.alignVert){addStyleSheet();var height=innerSpan.scrollHeight;if(window.getComputedStyle(el)["position"]==="static"){el.style["position"]="relative"}if(!hasClass(innerSpan,"textFitAlignVert")){innerSpan.className=innerSpan.className+" textFitAlignVert"}innerSpan.style["height"]=height+"px";if(settings.alignVertWithFlexbox&&!hasClass(el,"textFitAlignVertFlex")){el.className=el.className+" textFitAlignVertFlex"}}}function innerHeight(el){var style=window.getComputedStyle(el,null);return el.getBoundingClientRect().height-parseInt(style.getPropertyValue("padding-top"),10)-parseInt(style.getPropertyValue("padding-bottom"),10)}function innerWidth(el){var style=window.getComputedStyle(el,null);return el.getBoundingClientRect().width-parseInt(style.getPropertyValue("padding-left"),10)-parseInt(style.getPropertyValue("padding-right"),10)}function isElement(o){return typeof HTMLElement==="object"?o instanceof HTMLElement:o&&typeof o==="object"&&o!==null&&o.nodeType===1&&typeof o.nodeName==="string"}function hasClass(element,cls){return(" "+element.className+" ").indexOf(" "+cls+" ")>-1}function addStyleSheet(){if(document.getElementById("textFitStyleSheet"))return;var style=[".textFitAlignVert{","position: absolute;","top: 0; right: 0; bottom: 0; left: 0;","margin: auto;","display: flex;","justify-content: center;","flex-direction: column;","}",".textFitAlignVertFlex{","display: flex;","}",".textFitAlignVertFlex .textFitAlignVert{","position: static;","}"].join("");var css=document.createElement("style");css.type="text/css";css.id="textFitStyleSheet";css.innerHTML=style;document.body.appendChild(css)}});