diff --git a/src/language-graphql/printer-graphql.js b/src/language-graphql/printer-graphql.js
index 70f0df48a..8b7948804 100644
--- a/src/language-graphql/printer-graphql.js
+++ b/src/language-graphql/printer-graphql.js
@@ -653,7 +653,7 @@ function canAttachComment(node) {
 function printComment(commentPath) {
   const comment = commentPath.getValue();
   if (comment.kind === "Comment") {
-    return "#" + comment.value.trimRight();
+    return "#" + comment.value.trimEnd();
   }
 
   throw new Error("Not a comment: " + JSON.stringify(comment));
diff --git a/src/language-js/printer-estree.js b/src/language-js/printer-estree.js
index bc61c4a51..c6c48e660 100644
--- a/src/language-js/printer-estree.js
+++ b/src/language-js/printer-estree.js
@@ -241,7 +241,7 @@ function genericPrint(path, options, printPath, args) {
     const node = path.getValue();
     if (hasFlowShorthandAnnotationComment(node)) {
       parts.push(" /*");
-      parts.push(node.trailingComments[0].value.trimLeft());
+      parts.push(node.trailingComments[0].value.trimStart());
       parts.push("*/");
       node.trailingComments[0].printed = true;
     }
@@ -3560,7 +3560,7 @@ function printPathNoParens(path, options, print, args) {
           path.call(print, "node"),
           !n.node.comments || n.node.comments.length === 0
             ? []
-            : concat([" //", n.node.comments[0].value.trimRight()])
+            : concat([" //", n.node.comments[0].value.trimEnd()])
         )
       );
     case "NGChainedExpression":
@@ -6005,9 +6005,9 @@ function printComment(commentPath, options) {
       if (
         options.originalText.slice(options.locStart(comment)).startsWith("#!")
       ) {
-        return "#!" + comment.value.trimRight();
+        return "#!" + comment.value.trimEnd();
       }
-      return "//" + comment.value.trimRight();
+      return "//" + comment.value.trimEnd();
     default:
       throw new Error("Not a comment: " + JSON.stringify(comment));
   }
@@ -6031,8 +6031,8 @@ function printIndentableBlockComment(comment) {
       hardline,
       lines.map((line, index) =>
         index === 0
-          ? line.trimRight()
-          : " " + (index < lines.length - 1 ? line.trim() : line.trimLeft())
+          ? line.trimEnd()
+          : " " + (index < lines.length - 1 ? line.trim() : line.trimStart())
       )
     ),
     "*/"
diff --git a/src/language-markdown/pragma.js b/src/language-markdown/pragma.js
index 070fb50db..4ca546c0f 100644
--- a/src/language-markdown/pragma.js
+++ b/src/language-markdown/pragma.js
@@ -19,7 +19,8 @@ function startWithPragma(text) {
 
 module.exports = {
   startWithPragma,
-  hasPragma: text => startWithPragma(parseFrontMatter(text).content.trimLeft()),
+  hasPragma: text =>
+    startWithPragma(parseFrontMatter(text).content.trimStart()),
   insertPragma: text => {
     const extracted = parseFrontMatter(text);
     const pragma = `<!-- @${pragmas[0]} -->`;
diff --git a/src/language-markdown/preprocess.js b/src/language-markdown/preprocess.js
index 08caf1e91..edeaa09fd 100644
--- a/src/language-markdown/preprocess.js
+++ b/src/language-markdown/preprocess.js
@@ -120,10 +120,10 @@ function splitTextIntoSentences(ast, options) {
 
     if (parentNode.type === "paragraph") {
       if (index === 0) {
-        value = value.trimLeft();
+        value = value.trimStart();
       }
       if (index === parentNode.children.length - 1) {
-        value = value.trimRight();
+        value = value.trimEnd();
       }
     }
 
diff --git a/src/language-markdown/printer-markdown.js b/src/language-markdown/printer-markdown.js
index d00487ed4..6ab4fb4cb 100644
--- a/src/language-markdown/printer-markdown.js
+++ b/src/language-markdown/printer-markdown.js
@@ -230,7 +230,7 @@ function genericPrint(path, options, print) {
       const value =
         parentNode.type === "root" &&
         privateUtil.getLast(parentNode.children) === node
-          ? node.value.trimRight()
+          ? node.value.trimEnd()
           : node.value;
       const isHtmlComment = /^<!--[\s\S]*-->$/.test(value);
       return concat(
diff --git a/src/language-yaml/utils.js b/src/language-yaml/utils.js
index 8990f05c2..7a562f0bd 100644
--- a/src/language-yaml/utils.js
+++ b/src/language-yaml/utils.js
@@ -198,8 +198,8 @@ function getFlowScalarLineContents(nodeType, content, options) {
         : index !== 0 && index !== lineContents.length - 1
         ? lineContent.trim()
         : index === 0
-        ? lineContent.trimRight()
-        : lineContent.trimLeft()
+        ? lineContent.trimEnd()
+        : lineContent.trimStart()
     );
 
   if (options.proseWrap === "preserve") {
diff --git a/src/main/core.js b/src/main/core.js
index 4d6e98a61..7c2cc6e63 100644
--- a/src/main/core.js
+++ b/src/main/core.js
@@ -60,7 +60,7 @@ function attachComments(text, ast, opts) {
     comments.attach(astComments, ast, text, opts);
   }
   ast.tokens = [];
-  opts.originalText = opts.parser === "yaml" ? text : text.trimRight();
+  opts.originalText = opts.parser === "yaml" ? text : text.trimEnd();
   return astComments;
 }
 
@@ -221,7 +221,7 @@ function formatRange(text, opts) {
 
   // Since the range contracts to avoid trailing whitespace,
   // we need to remove the newline that was inserted by the `format` call.
-  const rangeTrimmed = rangeResult.formatted.trimRight();
+  const rangeTrimmed = rangeResult.formatted.trimEnd();
   const rangeLeft = text.slice(0, rangeStart);
   const rangeRight = text.slice(rangeEnd);