diff --git a/CHANGELOG.md b/CHANGELOG.md
index c6ba311..0ed0188 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,8 +4,8 @@ The URL structure has changed to make it possible to add more options. The old U
 
 Some examples:
 
-- `/scaled/500x500/foobar.jpg` -> `/scaled/width:500|height:500/foobar.jpg`
-- `/scaled/x400/foobar.jpg.webp` -> `/scaled/height:400|convert:webp/foobar.jpg.webp`
+- `/scaled/500x500/foobar.jpg` -> `/scaled/width:500_height:500/foobar.jpg`
+- `/scaled/x400/foobar.jpg.webp` -> `/scaled/height:400_convert:webp/foobar.jpg.webp`
 
 # Upgrade to V3
 
diff --git a/README.md b/README.md
index 9f7b9c6..261f0de 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,7 @@ Subsequent requests to the bucket will therefore skip the Lambda function entire
 
 The function will allow resizing of images, by width, height, or both dimensions. Example paths:
 
-- `/scaled/width:500|height:500/foobar.jpg`: this would generate a 500x500 version of the image `foobar.jpg`.
+- `/scaled/width:500_height:500/foobar.jpg`: this would generate a 500x500 version of the image `foobar.jpg`.
 - `/scaled/width:500/foobar.jpg`: omitting the `height` would generate a 500px wide version of the image.
 - `/scaled/height:500/foobar.jpg`: omitting the `width` would generate a 500px high version of the image.
 
@@ -50,7 +50,7 @@ The function will allow resizing of images, by width, height, or both dimensions
 
 You can convert an image to a different format.
 
-- `/scaled/width:500|height:500|convert:webp/foobar.jpg.webp`: this will create a **webp** version of the file `foobar.jpg`, scaled to 500x500.
+- `/scaled/width:500_height:500_convert:webp/foobar.jpg.webp`: this will create a **webp** version of the file `foobar.jpg`, scaled to 500x500.
 
 ## Versions
 
@@ -102,7 +102,7 @@ This package includes a local image server, allowing you to test with this image
 yarn serve
 ```
 
-Then use http://localhost:8888/scaled/width:500|height:500/foo/bar.jpg for your image requests.
+Then use http://localhost:8888/scaled/width:500_height:500/foo/bar.jpg for your image requests.
 
 Currently, you will get back a random image with the requested dimensions.
 
diff --git a/test/parseOptions.test.js b/test/parseOptions.test.js
index 3cf7400..821a38b 100644
--- a/test/parseOptions.test.js
+++ b/test/parseOptions.test.js
@@ -2,7 +2,7 @@ const parseOptions = require("../util/parseOptions.js");
 
 it("should parse the options", function () {
   expect(parseOptions("width:100")).toEqual({ width: "100" });
-  expect(parseOptions("width:100|height:200")).toEqual({
+  expect(parseOptions("width:100_height:200")).toEqual({
     width: "100",
     height: "200",
   });
diff --git a/test/pathToParams.test.js b/test/pathToParams.test.js
index c9e1feb..e48587c 100644
--- a/test/pathToParams.test.js
+++ b/test/pathToParams.test.js
@@ -5,7 +5,7 @@ const pathToParams = require("../util/pathToParams.js");
 describe("pathToParams", () => {
   describe("Given a URL with both dimensions and no output-format", () => {
     it("Will extract dimensions and use the original extension as outputFormat", () => {
-      const input = "scaled/width:500|height:320/foo.jpg";
+      const input = "scaled/width:500_height:320/foo.jpg";
       const [options, path] = pathToParams(input);
       expect(options.width).toBe("500");
       expect(options.height).toBe("320");
@@ -32,7 +32,7 @@ describe("pathToParams", () => {
   });
   describe("Given a URL with a longer directory path", () => {
     it("Will extract the correct path", () => {
-      const input = "/scaled/width:500|height:500/my/deeper/folder/foo.jpg";
+      const input = "/scaled/width:500_height:500/my/deeper/folder/foo.jpg";
       const [options, path] = pathToParams(input, ["jpg"]);
       expect(options.width).toBe("500");
       expect(options.height).toBe("500");
@@ -41,7 +41,7 @@ describe("pathToParams", () => {
   });
   describe("Given a file with a double extension", () => {
     it("Will treat the first extension as part of the original filename, and the last part as the outputFormat", () => {
-      const input = "/scaled/width:300|height:120|convert:png/foo.jpg.png";
+      const input = "/scaled/width:300_height:120_convert:png/foo.jpg.png";
       const [options, path] = pathToParams(input);
       const inputFormat = getInputFormat(path, options.convert);
       const outputFormat = getOutputFormat(path, options.convert);
@@ -52,7 +52,7 @@ describe("pathToParams", () => {
       expect(inputFormat).toBe("jpg");
     });
     it("Will be able to handle repeating extensions.", () => {
-      const input = "/scaled/width:300|height:120/foo.jpg.jpg";
+      const input = "/scaled/width:300_height:120/foo.jpg.jpg";
       const [options, path] = pathToParams(input);
       expect(options.width).toBe("300");
       expect(options.height).toBe("120");
diff --git a/util/parseOptions.js b/util/parseOptions.js
index 66aa61b..b8f794b 100644
--- a/util/parseOptions.js
+++ b/util/parseOptions.js
@@ -7,7 +7,7 @@
 module.exports = (optionsString) => {
   let options = {};
 
-  optionsString.split("|").forEach((option) => {
+  optionsString.split("_").forEach((option) => {
     const [action, ...params] = option.split(":");
     // Currently only one parameter is supported.
     options[action] = params[0];