diff --git a/README.md b/README.md
index f57ce0f..167b5dc 100644
--- a/README.md
+++ b/README.md
@@ -49,6 +49,25 @@ I hope it works`,
 });
 ```
 
+If you want to upload non-text data, you can `base64`` encode the content and provide that as the value. Here's an example that would upload a small GitHub icon to a repository:
+
+```javascript
+const commits = await octokit.rest.repos.createOrUpdateFiles({
+  owner,
+  repo,
+  branch,
+  createBranch,
+  changes: [
+    {
+      message: "Add Icon",
+      files: {
+            "icon.png": `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`
+      }
+    },
+  ],
+});
+```
+
 In addition, you can set the `mode` of a file change. For example, if you wanted to update a submodule pointer:
 
 ```javascript
diff --git a/create-or-update-files.js b/create-or-update-files.js
index 5f7f60f..c1391f7 100644
--- a/create-or-update-files.js
+++ b/create-or-update-files.js
@@ -1,3 +1,4 @@
+const isBase64 = require("is-base64");
 module.exports = function(octokit, opts) {
   return new Promise(async (resolve, reject) => {
     // Up front validation
@@ -247,11 +248,17 @@ async function createBlob(octokit, owner, repo, contents, type) {
   if (type === "commit") {
     return contents;
   } else {
+    let content = contents;
+
+    if (!isBase64(content)) {
+      content = Buffer.from(contents).toString("base64");
+    }
+
     const file = (
       await octokit.rest.git.createBlob({
         owner,
         repo,
-        content: Buffer.from(contents).toString("base64"),
+        content,
         encoding: "base64"
       })
     ).data;
diff --git a/create-or-update-files.test.js b/create-or-update-files.test.js
index b27c7df..95936d0 100644
--- a/create-or-update-files.test.js
+++ b/create-or-update-files.test.js
@@ -189,6 +189,31 @@ test(`success (branch exists)`, async () => {
   await expect(run(body)).resolves.toEqual(mockCommitList);
 });
 
+test(`success (base64 encoded body)`, async () => {
+  const body = {
+    ...validRequest,
+    changes: [
+      {
+        message: "Your commit message",
+        files: {
+          "test.md": "SGVsbG8gV29ybGQ=",
+          "test2.md": {
+            contents: `Something else`
+          }
+        }
+      }
+    ]
+  };
+  mockGetRef(branch, `sha-${branch}`, true);
+  mockCreateBlobBase64PreEncoded();
+  mockCreateBlobFileTwo();
+  mockCreateTree(`sha-${branch}`);
+  mockCommit(`sha-${branch}`);
+  mockUpdateRef(branch);
+
+  await expect(run(body)).resolves.toEqual(mockCommitList);
+});
+
 test(`success (committer details)`, async () => {
   const committer = {
     name: "Ashley Person",
@@ -469,6 +494,13 @@ function mockCreateBlobFileFour() {
   return mockCreateBlob("aGk=", "f65b65200aea4fecbe0db6ddac1c0848cdda1d9b");
 }
 
+function mockCreateBlobBase64PreEncoded() {
+  return mockCreateBlob(
+    "SGVsbG8gV29ybGQ=",
+    "afb296bb7f3e327767bdda481c4877ba4a09e02e"
+  );
+}
+
 function mockCreateTreeSubmodule(baseTree) {
   const expectedBody = {
     tree: [
diff --git a/package-lock.json b/package-lock.json
index d78a058..77f9802 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -6,9 +6,10 @@
   "packages": {
     "": {
       "name": "octokit-commit-multiple-files",
-      "version": "3.2.1",
+      "version": "4.0.0",
       "license": "MIT",
       "dependencies": {
+        "is-base64": "^1.1.0",
         "nock": "^11.7.0"
       },
       "devDependencies": {
@@ -2571,6 +2572,15 @@
       "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
       "dev": true
     },
+    "node_modules/is-base64": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/is-base64/-/is-base64-1.1.0.tgz",
+      "integrity": "sha512-Nlhg7Z2dVC4/PTvIFkgVVNvPHSO2eR/Yd0XzhGiXCXEvWnptXlXa/clQ8aePPiMuxEGcWfzWbGw2Fe3d+Y3v1g==",
+      "bin": {
+        "is_base64": "bin/is-base64",
+        "is-base64": "bin/is-base64"
+      }
+    },
     "node_modules/is-core-module": {
       "version": "2.8.1",
       "resolved": "https://registry.npmjs.org/is-core-module/-/is-core-module-2.8.1.tgz",
@@ -6727,6 +6737,11 @@
       "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ==",
       "dev": true
     },
+    "is-base64": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/is-base64/-/is-base64-1.1.0.tgz",
+      "integrity": "sha512-Nlhg7Z2dVC4/PTvIFkgVVNvPHSO2eR/Yd0XzhGiXCXEvWnptXlXa/clQ8aePPiMuxEGcWfzWbGw2Fe3d+Y3v1g=="
+    },
     "is-core-module": {
       "version": "2.8.1",
       "resolved": "https://registry.npmjs.org/is-core-module/-/is-core-module-2.8.1.tgz",
diff --git a/package.json b/package.json
index 760cef7..6a84a8f 100644
--- a/package.json
+++ b/package.json
@@ -24,6 +24,7 @@
     "prettier": "^1.19.1"
   },
   "dependencies": {
+    "is-base64": "^1.1.0",
     "nock": "^11.7.0"
   },
   "peerDependencies": {