Skip to content
WinBookUnofficial

Windows 11 ISO: download, verify SHA-256, identify the build

Verified 2 min read

Get the official Windows 11 26H2 ISO, record its SHA-256, compare it with the hash published by your source, and avoid modified images.

Tested onPro (26H2) · Build 26300.9457 · x64
E2
Build
26300.9457
Edition
Pro (26H2)
Architecture
x64
Support
Lab (ISO verified)
Evidence
E2Reproduced in the lab
Verified
2026-10-28
Test machine
Lab ISO Windows11_Client_x64_en-us_26300_9457.iso; SHA-256 verified before install
Page type
Task

The short answer

Section titled “The short answer”

Download Windows 11 from Microsoft’s official page or your volume-licensing portal. Record the filename, size and SHA-256. Compare the hash against the hash published by the same source you downloaded from.

A matching hash proves the file did not change after the hash was published. It does not prove that a random mirror is safe. If the source does not publish a hash, your own recorded hash is a baseline for re-downloads, not an authenticity check.

1. Get the right artifact

Section titled “1. Get the right artifact”
Field What to record Example
Release 26H2 Annual 2026 feature update
Architecture x64 or Arm64 Must match the PC
Language en-us, zh-cn, … Match your intended UI
Edition Home/Pro/Enterprise/LTSC The ISO may contain multiple editions
Filename Exact name Windows11_Client_x64_en-us_26300_9457.iso
Size Bytes 9,047,330,816 bytes in our lab
SHA-256 64 hex characters BD4307…A650 in our lab

Our lab image hashes to:

BD4307DF32BC8AF33B39CCECB1174AEB345386630F89A2B86C7A4E36B55EA650

That is the hash of our English x64 26H2 ISO. A different language, architecture, edition or update level will have a different hash. Do not copy this value onto a different file and call it verified.

2. Hash it on Windows

Section titled “2. Hash it on Windows”
Terminal window
Get-FileHash .\Windows11_Client_x64_en-us_26300_9457.iso -Algorithm SHA256

Or, from Command Prompt:

Terminal window
certutil -hashfile Windows11_Client_x64_en-us_26300_9457.iso SHA256

Compare the entire 64-character value, not the first eight characters. Case does not matter.

3. Hash it on Linux or macOS

Section titled “3. Hash it on Linux or macOS”
Terminal window
sha256sum Windows11_Client_x64_en-us_26300_9457.iso
Terminal window
shasum -a 256 Windows11_Client_x64_en-us_26300_9457.iso

4. Check what the image actually is

Section titled “4. Check what the image actually is”

Mount the ISO and inspect the sources folder:

  • sources/install.wim or sources/install.esd should exist.
  • setup.exe should be present.
  • The ISO should report the expected Windows release when you run Setup.

If the file is an ESD-only “recovery” image or a vendor recovery disk, it may not behave like a clean-install ISO. Do not mix recovery media with a clean install guide.

5. If the hash does not match

Section titled “5. If the hash does not match”
  1. Re-download from the same official source. A partial download is the most common cause.
  2. Check the file size against the source.
  3. Try a different browser or download manager only if the source supports resumable downloads.
  4. If the source publishes a hash and it still does not match, stop. Do not install the image.

Lab note

Section titled “Lab note”

We downloaded the English x64 26H2 ISO, recorded 9,047,330,816 bytes, and verified SHA-256 BD4307…A650 before the clean install. The install then reported build 26300.9457. Hash verification and build verification are separate checks; do both.

Scope: x64 English 26H2 ISO only. We did not verify Arm64, other languages or 25H2 media on this page.

Sources