How to Download macOS High Sierra

Overview and Quick Summary

macOS High Sierra (version 10.13) is an older but still supported major release that introduced security, performance, and media foundation updates. This guide explains how to download High Sierra from official sources, which Mac models are compatible, and how to prepare and perform a clean or in-place installation. Topics include verifying app integrity, creating bootable installers, and essential backup steps. The content is structured as an evergreen reference so you can safely install or reinstall High Sierra today with minimal risk.

Official Download Sources and Methods

The most reliable way to obtain macOS High Sierra is through the Mac App Store on a compatible Mac. Apple no longer提供 direct download links on its support page, so using an authorized device ensures you receive the genuine, cryptographically signed installer. You can also create a bootable installer using the createinstallmedia command in Terminal, which is valuable for clean installations or multiple machines.

Use the Mac App Store on a Mac running any recent macOS to access High Sierra as a previous macOS version.
Download the installer once; you can re-use it without repeated network fetches.
For advanced users, build a bootable USB installer to bypass upgrade logic and perform archive installs.

How to Download via the Mac App Store

Open the App Store app on a compatible Mac connected to the Internet.
Search for “macOS High Sierra”.
Select “Get” and confirm your identity with your Apple ID password or biometric auth.
Installations downloaded this way appear in Applications as Install macOS High Sierra.app.

Verify Installer Integrity (Quick Checks)

Confirm the app is signed by Apple by opening Finder, selecting the installer, and choosing File → Get Info.
Check size: the High Sierra installer is approximately 3.0–4.0 GB depending on build.
Match checksums if published by Apple in security updates (rare for older releases).

macOS High Sierra Compatibility and Requirements

High Sierra supports a broad set of Macs introduced from around 2009 through mid-2012. Before attempting a download or install, confirm compatibility to avoid errors and hardware feature limitations.

Category	Verified Detail	Source Type
Oldest Supported Models	MacBook (Early 2009), iMac (Late 2009), MacBook Pro (Mid 2010)	Apple Knowledge Base
Recommended Minimum RAM	4 GB; 8 GB preferred for smoother experience	Apple System Requirements
Minimum Free Storage	8–12 GB available for install; more for updates and apps	Apple System Requirements
Graphics and Features	Metal API introduced; some features require compatible GPUs	Apple Release Notes

Model Identification Tips

Choose Apple menu > About This Mac to see the model identifier and year.
Cross-reference identifiers on Apple Support to confirm High Sierra eligibility.
If your Mac supports High Sierra, it also supports later updates, which may offer newer security fixes.

Preparation: Backups and Pre-Install Checklist

Before downloading and installing, reduce risk with verified backups and basic checks. Even on older systems, a careful approach prevents data loss and configuration problems.

Back up with Time Machine: Use an external drive for a full system snapshot.
Verify storage health: Open Disk Utility and run First Aid on your startup disk.
Disconnect nonessential peripherals: Keep keyboard, mouse, and display; remove printers or custom firmware devices temporarily.
Note Apple ID and passwords: Required for activation, App Store, and iCloud during setup.
Power and battery: Use AC power; laptops should be above 50% battery before starting.

Installing macOS High Sierra: Step-by-Step

You can install High Sierra in two ways: in-place upgrade (keeps user data and apps) or clean install (wipes the disk and installs fresh). Choose the method that matches your goals and backup readiness.

In-Place Upgrade (Standard Method)

Open the Install macOS High Sierra app you downloaded.
Agree to the license agreement and select the startup disk (usually named Macintosh HD).
Let the installer copy files, restart, and complete configuration; your user data remains intact.
After reboot, log in and run Software Update once to pull any High Sierra patch updates.

Clean Installation with Bootable Installer

Create a bootable USB installer on another Mac using the createinstallmedia command.
Insert the USB, restart your Mac, and hold Option (Alt) to choose the USB as the boot volume.
Open Disk Utility, select the target disk, and click Erase to APFS or Mac OS Extended (Journaled).
Quit Disk Utility and run Install macOS from the installer menu; this performs a fresh install.
After setup, restore files selectively from your Time Machine backup.

Post-Installation: Activation, Updates, and Optimization

Once High Sierra is running, finalize setup and keep the system secure. Note that some newer apps and features may be limited compared to later macOS releases, but core functionality remains reliable.

First Steps After Install

Sign in with your Apple ID to enable iCloud, App Store, and automatic updates.
Run Software Update under System Preferences to install the latest High Sevens fixes.
Confirm peripheral drivers and firmware are current, especially for printers and external GPUs.
Reconfigure energy, sound, and network settings to match your preferences.

Performance and Maintenance Tips

Schedule periodic Disk Utility First Aid and verify permissions when unusual behavior occurs.
Keep at least 10–15% free space on the startup disk for temporary files and updates.
Review Login Items in Users & Groups to disable unnecessary background apps.
If you experience instability, consider reinstalling macOS in place before resorting to clean installs.

If High Sierra no longer meets your needs or your Mac is incompatible, consider supported macOS releases that receive current security updates. Evaluate your workflow, app compatibility, and hardware limits before deciding to upgrade or stay on High Sierra.

Test critical apps in a separate user account before committing to a system-wide upgrade.
Check app minimum OS requirements; some developers drop support for older macOS versions.
For legacy hardware, a clean High Sierra install can provide stability and predictable performance.

Conclusion

Downloading and installing macOS High Sierra is straightforward when you use official sources, verify compatibility, and prepare backups. Whether you choose an in-place upgrade or a clean install, following these steps helps ensure a stable, secure system. Treat High Sierra as a maintained option if it meets your needs, but plan for eventual migration to newer macOS releases for ongoing security and feature improvements.