diff --git a/.changeset/nice-crabs-compete.md b/.changeset/nice-crabs-compete.md
new file mode 100644
index 0000000000..0fb860cbab
--- /dev/null
+++ b/.changeset/nice-crabs-compete.md
@@ -0,0 +1,5 @@
+---
+"uploadthing": minor
+---
+
+feat: return object hash in onUploadComplete
diff --git a/examples/minimal-appdir/src/server/uploadthing.ts b/examples/minimal-appdir/src/server/uploadthing.ts
index c6c43ba817..981ac16f8b 100644
--- a/examples/minimal-appdir/src/server/uploadthing.ts
+++ b/examples/minimal-appdir/src/server/uploadthing.ts
@@ -36,8 +36,6 @@ export const uploadRouter = {
   })
     .middleware(({ req, files }) => {
       // Check some condition based on the incoming requrest
-      console.log("Request", req);
-      //^?
       // if (!req.headers.get("x-some-header")) {
       //   throw new Error("x-some-header is required");
       // }
diff --git a/examples/minimal-pagedir/src/server/uploadthing.ts b/examples/minimal-pagedir/src/server/uploadthing.ts
index 95580c5ec1..b635168a09 100644
--- a/examples/minimal-pagedir/src/server/uploadthing.ts
+++ b/examples/minimal-pagedir/src/server/uploadthing.ts
@@ -30,8 +30,6 @@ export const uploadRouter = {
   })
     .middleware(({ req }) => {
       // Check some condition based on the incoming requrest
-      req;
-      //^?
       // if (!req.headers["x-some-header"]) {
       //   throw new Error("x-some-header is required");
       // }
diff --git a/examples/minimal-solidstart/src/server/uploadthing.ts b/examples/minimal-solidstart/src/server/uploadthing.ts
index 1e0941de0c..5812840e77 100644
--- a/examples/minimal-solidstart/src/server/uploadthing.ts
+++ b/examples/minimal-solidstart/src/server/uploadthing.ts
@@ -30,8 +30,6 @@ export const uploadRouter = {
   })
     .middleware(({ req }) => {
       // Check some condition based on the incoming request
-      req;
-      //^?
       // if (!req.headers.get("x-some-header")) {
       //   throw new Error("x-some-header is required");
       // }
diff --git a/examples/minimal-sveltekit/src/lib/server/uploadthing.ts b/examples/minimal-sveltekit/src/lib/server/uploadthing.ts
index 6b32c8872c..32641c373d 100644
--- a/examples/minimal-sveltekit/src/lib/server/uploadthing.ts
+++ b/examples/minimal-sveltekit/src/lib/server/uploadthing.ts
@@ -33,8 +33,6 @@ export const uploadRouter = {
   })
     .middleware(({ req, files }) => {
       // Check some condition based on the incoming requrest
-      req;
-      //^?
       // if (!req.headers.get("x-some-header")) {
       //   throw new Error("x-some-header is required");
       // }
diff --git a/examples/with-drizzle-appdir/src/server/uploadthing.ts b/examples/with-drizzle-appdir/src/server/uploadthing.ts
index 3bfdd76d44..36801d6600 100644
--- a/examples/with-drizzle-appdir/src/server/uploadthing.ts
+++ b/examples/with-drizzle-appdir/src/server/uploadthing.ts
@@ -35,8 +35,6 @@ export const uploadRouter = {
   })
     .middleware(({ req }) => {
       // Check some condition based on the incoming requrest
-      req;
-      //^?
       // if (!req.headers.get("x-some-header")) {
       //   throw new Error("x-some-header is required");
       // }
diff --git a/examples/with-drizzle-pagesdir/src/server/uploadthing.ts b/examples/with-drizzle-pagesdir/src/server/uploadthing.ts
index aabdd7740b..8d884a0ae0 100644
--- a/examples/with-drizzle-pagesdir/src/server/uploadthing.ts
+++ b/examples/with-drizzle-pagesdir/src/server/uploadthing.ts
@@ -33,8 +33,6 @@ export const uploadRouter = {
   })
     .middleware(({ req }) => {
       // Check some condition based on the incoming requrest
-      req;
-      //^?
       // if (!req.headers.get("x-some-header")) {
       //   throw new Error("x-some-header is required");
       // }
diff --git a/examples/with-react-image-crop/src/server/uploadthing.ts b/examples/with-react-image-crop/src/server/uploadthing.ts
index f239c2822f..a063885f0e 100644
--- a/examples/with-react-image-crop/src/server/uploadthing.ts
+++ b/examples/with-react-image-crop/src/server/uploadthing.ts
@@ -27,8 +27,6 @@ export const uploadRouter = {
   })
     .middleware(({ req }) => {
       // Check some condition based on the incoming requrest
-      req;
-      //^?
       // if (!req.headers.get("x-some-header")) {
       //   throw new Error("x-some-header is required");
       // }
diff --git a/examples/with-tailwindcss/src/server/uploadthing.ts b/examples/with-tailwindcss/src/server/uploadthing.ts
index 306321ca8c..b79ce4e4a9 100644
--- a/examples/with-tailwindcss/src/server/uploadthing.ts
+++ b/examples/with-tailwindcss/src/server/uploadthing.ts
@@ -30,8 +30,6 @@ export const uploadRouter = {
   })
     .middleware(({ req }) => {
       // Check some condition based on the incoming requrest
-      req;
-      //^?
       // if (!req.headers.get("x-some-header")) {
       //   throw new Error("x-some-header is required");
       // }
diff --git a/packages/nuxt/playground/server/uploadthing.ts b/packages/nuxt/playground/server/uploadthing.ts
index 9d74caeb3c..cf7272dcc0 100644
--- a/packages/nuxt/playground/server/uploadthing.ts
+++ b/packages/nuxt/playground/server/uploadthing.ts
@@ -30,8 +30,6 @@ export const uploadRouter = {
   })
     .middleware(({ req }) => {
       // Check some condition based on the incoming requrest
-      req;
-      //^?
       // if (!req.headers.get("x-some-header")) {
       //   throw new Error("x-some-header is required");
       // }
diff --git a/packages/uploadthing/src/internal/shared-schemas.ts b/packages/uploadthing/src/internal/shared-schemas.ts
index e8f215efad..cbac8755dd 100644
--- a/packages/uploadthing/src/internal/shared-schemas.ts
+++ b/packages/uploadthing/src/internal/shared-schemas.ts
@@ -71,6 +71,7 @@ export class FileUploadDataWithCustomId extends FileUploadData.extend<FileUpload
  * - a key
  * - a direct URL for the file
  * - an app-specific URL for the file (useful for scoping eg. for optimization allowed origins)
+ * - the hash (md5-hex) of the uploaded file's contents
  */
 export class UploadedFileData extends FileUploadDataWithCustomId.extend<UploadedFileData>(
   "UploadedFileData",
@@ -78,6 +79,7 @@ export class UploadedFileData extends FileUploadDataWithCustomId.extend<Uploaded
   key: S.String,
   url: S.String,
   appUrl: S.String,
+  fileHash: S.String,
 }) {}
 
 /**
diff --git a/packages/uploadthing/src/internal/types.ts b/packages/uploadthing/src/internal/types.ts
index daebb085c7..b284ee7771 100644
--- a/packages/uploadthing/src/internal/types.ts
+++ b/packages/uploadthing/src/internal/types.ts
@@ -236,3 +236,13 @@ export type UTEvents = {
     out: ReadonlyArray<NewPresignedUrl>;
   };
 };
+
+/**
+ * Result from the PUT request to the UploadThing Ingest server
+ */
+export type UploadPutResult<TServerOutput = unknown> = {
+  url: string;
+  appUrl: string;
+  fileHash: string;
+  serverData: TServerOutput;
+};
diff --git a/packages/uploadthing/src/internal/upload.browser.ts b/packages/uploadthing/src/internal/upload.browser.ts
index bb999a8339..ad5a75aee3 100644
--- a/packages/uploadthing/src/internal/upload.browser.ts
+++ b/packages/uploadthing/src/internal/upload.browser.ts
@@ -11,6 +11,7 @@ import type {
   NewPresignedUrl,
   UploadFilesOptions,
 } from "../types";
+import type { UploadPutResult } from "./types";
 import { createUTReporter } from "./ut-reporter";
 
 const uploadWithProgress = (
@@ -92,12 +93,7 @@ export const uploadFile = <
         }),
       ),
     ),
-    Micro.map(
-      unsafeCoerce<
-        unknown,
-        { url: string; appUrl: string; serverData: TServerOutput }
-      >,
-    ),
+    Micro.map(unsafeCoerce<unknown, UploadPutResult<TServerOutput>>),
     Micro.map((uploadResponse) => ({
       name: file.name,
       size: file.size,
@@ -108,6 +104,7 @@ export const uploadFile = <
       appUrl: uploadResponse.appUrl,
       customId: presigned.customId,
       type: file.type,
+      fileHash: uploadResponse.fileHash,
     })),
   );
 
diff --git a/packages/uploadthing/src/internal/upload.server.ts b/packages/uploadthing/src/internal/upload.server.ts
index 8d4f994466..aaa882107a 100644
--- a/packages/uploadthing/src/internal/upload.server.ts
+++ b/packages/uploadthing/src/internal/upload.server.ts
@@ -9,6 +9,7 @@ import { unsafeCoerce } from "effect/Function";
 import { UploadThingError } from "@uploadthing/shared";
 
 import type { FileEsque } from "../sdk/types";
+import type { UploadPutResult } from "./types";
 
 export const uploadWithoutProgress = (
   file: FileEsque,
@@ -32,8 +33,7 @@ export const uploadWithoutProgress = (
           }),
       ),
       HttpClientResponse.json,
-
-      Effect.andThen(unsafeCoerce<unknown, { url: string; appUrl: string }>),
+      Effect.andThen(unsafeCoerce<unknown, UploadPutResult>),
     );
 
     yield* Effect.logDebug(`File ${file.name} uploaded successfully`).pipe(
diff --git a/packages/uploadthing/src/sdk/utils.ts b/packages/uploadthing/src/sdk/utils.ts
index a5c4e81902..55ceb9446e 100644
--- a/packages/uploadthing/src/sdk/utils.ts
+++ b/packages/uploadthing/src/sdk/utils.ts
@@ -178,16 +178,17 @@ const uploadFile = (
   Effect.gen(function* () {
     const { file, presigned } = input;
 
-    const { url, appUrl } = yield* uploadWithoutProgress(file, presigned);
+    const response = yield* uploadWithoutProgress(file, presigned);
 
     return {
       key: presigned.key,
-      url: url,
-      appUrl: appUrl,
+      url: response.url,
+      appUrl: response.appUrl,
       lastModified: file.lastModified ?? Date.now(),
       name: file.name,
       size: file.size,
       type: file.type,
       customId: file.customId ?? null,
+      fileHash: response.fileHash,
     };
   }).pipe(Effect.withLogSpan("uploadFile"));
diff --git a/packages/uploadthing/test/__test-helpers.ts b/packages/uploadthing/test/__test-helpers.ts
index 7e6f27a914..95dfb49d5a 100644
--- a/packages/uploadthing/test/__test-helpers.ts
+++ b/packages/uploadthing/test/__test-helpers.ts
@@ -1,3 +1,4 @@
+import { createHash } from "crypto";
 import * as S from "@effect/schema/Schema";
 import type { StrictRequest } from "msw";
 import { http, HttpResponse } from "msw";
@@ -7,6 +8,7 @@ import { afterAll, beforeAll, it as itBase, vi } from "vitest";
 import { UPLOADTHING_VERSION } from "../src/internal/config";
 import { ParsedToken, UploadThingToken } from "../src/internal/shared-schemas";
 import type { ActionType } from "../src/internal/shared-schemas";
+import type { UploadPutResult } from "../src/internal/types";
 
 export const requestSpy = vi.fn<(url: string, req: RequestInit) => void>();
 export const requestsToDomain = (domain: string) =>
@@ -115,10 +117,13 @@ export const it = itBase.extend({
         async ({ request, params }) => {
           await callRequestSpy(request);
           const appId = new URLSearchParams(request.url).get("x-ut-identifier");
-          return HttpResponse.json({
+          return HttpResponse.json<UploadPutResult>({
             url: `${UTFS_IO_URL}/f/${params.key}`,
             appUrl: `${UTFS_IO_URL}/a/${appId}/${params.key}`,
             serverData: null,
+            fileHash: createHash("md5")
+              .update(new Uint8Array(await request.arrayBuffer()))
+              .digest("hex"),
           });
         },
       ),
diff --git a/packages/uploadthing/test/client.test.ts b/packages/uploadthing/test/client.test.ts
index 2d72bc8fb8..5e3e189192 100644
--- a/packages/uploadthing/test/client.test.ts
+++ b/packages/uploadthing/test/client.test.ts
@@ -132,6 +132,7 @@ describe("uploadFiles", () => {
         key: expect.stringMatching(/.+/),
         url: expect.stringMatching(fileUrlPattern),
         appUrl: expect.stringMatching(appUrlPattern()),
+        fileHash: expect.any(String),
       },
     ]);
 
@@ -177,6 +178,7 @@ describe("uploadFiles", () => {
         key: expect.stringMatching(/.+/),
         url: expect.stringMatching(fileUrlPattern),
         appUrl: expect.stringMatching(appUrlPattern()),
+        fileHash: expect.any(String),
       },
     ]);
 
@@ -211,6 +213,7 @@ describe("uploadFiles", () => {
         key: expect.stringMatching(/.+/),
         url: expect.stringMatching(fileUrlPattern),
         appUrl: expect.stringMatching(appUrlPattern()),
+        fileHash: expect.any(String),
       },
     ]);
 
diff --git a/packages/uploadthing/test/request-handler.test.ts b/packages/uploadthing/test/request-handler.test.ts
index ca85767bca..c68bfef3d0 100644
--- a/packages/uploadthing/test/request-handler.test.ts
+++ b/packages/uploadthing/test/request-handler.test.ts
@@ -337,6 +337,7 @@ describe(".onUploadComplete()", () => {
         size: 48,
         type: "image/png",
         customId: null,
+        fileHash: "some-md5-hash",
       }),
     });
     const signature = await Effect.runPromise(
@@ -366,6 +367,7 @@ describe(".onUploadComplete()", () => {
         type: "image/png",
         url: "https://utfs.io/f/some-random-key.png",
         appUrl: `https://utfs.io/a/${testToken.decoded.appId}/some-random-key.png`,
+        fileHash: "some-md5-hash",
       },
       metadata: {},
     });
@@ -383,6 +385,7 @@ describe(".onUploadComplete()", () => {
         size: 48,
         type: "image/png",
         customId: null,
+        fileHash: "some-md5-hash",
       }),
     });
 
@@ -415,6 +418,7 @@ describe(".onUploadComplete()", () => {
         size: 48,
         type: "image/png",
         customId: null,
+        fileHash: "some-md5-hash",
       }),
     });
     const signature = await Effect.runPromise(
diff --git a/packages/uploadthing/test/sdk.test.ts b/packages/uploadthing/test/sdk.test.ts
index b74803d3e5..61edb8d555 100644
--- a/packages/uploadthing/test/sdk.test.ts
+++ b/packages/uploadthing/test/sdk.test.ts
@@ -54,6 +54,7 @@ describe("uploadFiles", () => {
         appUrl: `${UTFS_IO_URL}/a/${testToken.decoded.appId}/${key}`,
         customId: null,
         type: "text/plain",
+        fileHash: expect.any(String),
       },
       error: null,
     });
@@ -136,6 +137,7 @@ describe("uploadFilesFromUrl", () => {
         appUrl: `${UTFS_IO_URL}/a/${testToken.decoded.appId}/${key}`,
         customId: null,
         type: "text/plain",
+        fileHash: expect.any(String),
       },
       error: null,
     });
@@ -235,6 +237,7 @@ describe("uploadFilesFromUrl", () => {
           type: "text/plain",
           url: `${UTFS_IO_URL}/f/${key1}`,
           appUrl: `${UTFS_IO_URL}/a/${testToken.decoded.appId}/${key1}`,
+          fileHash: expect.any(String),
         },
         error: null,
       },
@@ -257,6 +260,7 @@ describe("uploadFilesFromUrl", () => {
           type: "text/plain",
           url: `${UTFS_IO_URL}/f/${key2}`,
           appUrl: `${UTFS_IO_URL}/a/${testToken.decoded.appId}/${key2}`,
+          fileHash: expect.any(String),
         },
         error: null,
       },
@@ -473,6 +477,7 @@ describe.runIf(shouldRun)(
           type: "text/plain",
           url: expect.stringMatching(fileUrlPattern),
           appUrl: expect.stringMatching(appUrlPattern(appId)),
+          fileHash: expect.any(String),
         },
         error: null,
       });
@@ -508,6 +513,7 @@ describe.runIf(shouldRun)(
           type: "text/plain",
           url: expect.stringMatching(fileUrlPattern),
           appUrl: expect.stringMatching(appUrlPattern(appId)),
+          fileHash: expect.any(String),
         },
         error: null,
       });
@@ -538,6 +544,7 @@ describe.runIf(shouldRun)(
           type: "image/vnd.microsoft.icon",
           url: expect.stringMatching(fileUrlPattern),
           appUrl: expect.stringMatching(appUrlPattern(appId)),
+          fileHash: expect.any(String),
         },
         error: null,
       });
@@ -563,6 +570,7 @@ describe.runIf(shouldRun)(
           type: "text/plain",
           url: expect.stringMatching(fileUrlPattern),
           appUrl: expect.stringMatching(appUrlPattern(appId)),
+          fileHash: expect.any(String),
         },
         error: null,
       });
@@ -605,6 +613,7 @@ describe.runIf(shouldRun)(
           type: "text/plain",
           url: expect.stringMatching(fileUrlPattern),
           appUrl: expect.stringMatching(appUrlPattern(appId)),
+          fileHash: expect.any(String),
         },
         error: null,
       });
@@ -645,6 +654,7 @@ describe.runIf(shouldRun)(
           type: "text/plain",
           url: expect.stringMatching(fileUrlPattern),
           appUrl: expect.stringMatching(appUrlPattern(appId)),
+          fileHash: expect.any(String),
         },
         error: null,
       });