Office 32-bit or 64-bit: what Microsoft recommends

Install Office as 32-bit or 64-bit? In almost all cases 64-bit. Microsoft recommends 64-bit on devices with at least 4 GB of memory, and current Office versions install this version by themselves. 32-bit is right above all if you use older add-ins, controls or Access files that are only available for 32-bit, or if the computer has less than 4 GB of memory. You choose the version during installation, not when you buy.

Quick decision

Your situation	Recommendation
Normal office or home PC with 4 GB of memory or more	64-bit
Large Excel workbooks, Power Pivot, many data connections	64-bit
Display with 4K resolution or higher	64-bit (required according to Microsoft)
Project files over 2 GB	64-bit
COM add-in or control only available for 32-bit	32-bit
Compiled Access files (.mde, .ade, .accde) from 32-bit	32-bit
Less than 4 GB of memory	32-bit
Mac	no choice, Office for Mac is available in 64-bit only

What the difference means

“Bit” here describes how much memory a program can address. According to Microsoft, a 32-bit program may have only 2 GB of virtual address space available, which it shares with all loaded add-ins. If the space is not enough, the program stops responding or crashes. A 64-bit program can use far more memory; Microsoft names up to 128 TB of virtual address space.

For letters and small spreadsheets you will notice nothing of this. The difference shows with large amounts of data and many extensions.

Reasons for 64-bit

Microsoft names these cases in which 64-bit is the right choice:

Large amounts of data in Excel: extensive workbooks with complex calculations, many PivotTables, connections to external databases, Power Pivot, 3D Maps or “Get & Transform”.
Add-ins in Outlook, Excel or other programs: with 64-bit, the program and add-ins share a very much larger address space.
Very large pictures, videos or animations in PowerPoint.
Project files over 2 GB, especially with many subprojects.
In-house development: if you develop add-ins or customizations for your company, you can ship and test both versions with 64-bit.
The “Large Number” data type in Access: it is supported with 32-bit, but can lead to unexpected results there in code and expressions.

Reasons for 32-bit

According to Microsoft, 32-bit is mandatory on systems with a 32-bit operating system and x86 processor and with less than 4 GB of memory. There are also cases in which 32-bit remains the better choice, even on 64-bit Windows:

COM add-ins without a 64-bit version. Ask the vendor for a 64-bit version; if there is none, 32-bit remains.
32-bit controls without a replacement, such as the older Windows Common Controls (Mscomctl.ocx, comctl.ocx) or controls from other vendors.
VBA code with Declare statements. Most macros run unchanged. Only code that calls Windows functions with 32-bit data types has to be adapted (PtrSafe, LongPtr).
32-bit MAPI applications for Outlook.
32-bit OLE servers or objects.
Compiled Access databases (.mde, .ade, .accde) from a 32-bit version. They can be recompiled; until that has been done, they only run with 32-bit Access.
The old Equation Editor or WLL files in Word.
Old embedded media files in PowerPoint, for which there is no 64-bit codec.

Important for everyone: add-ins and compiled Access files from a 32-bit version do not run in 64-bit Office, and vice versa.

What Office installs by itself

Version	Default during installation
Microsoft 365, Office 2024, Office 2021, Office 2019	64-bit
Office 2016	32-bit

One exception: if the installation already finds a 32-bit Office program on the computer, such as Project or Visio, it also installs 32-bit, according to Microsoft. All Office programs on one device must have the same version.

Office 2024 and Office LTSC 2024 are available for Windows in both versions. On ARM devices, Windows 11 is the oldest supported operating system.

How to check your version

Open an Office program, for example Word.
Select File › Account.
Select the button with the information about the program (About Word). A window shows the full version number and the bit version, i.e. 32-bit or 64-bit.

How to change the version

A direct switch is not possible. You must first remove Office completely:

Uninstall Office via Settings › Apps, including individually installed programs such as Project or Visio.
Restart the computer.
Reinstall Office and choose the desired version before the installation starts. With Office with a Microsoft account, you sign in to the account and choose language and version (64-bit or 32-bit) in the installation window, see Install Office: redeem the key.
With Office Professional Plus, Project and Visio, you set the version during installation. With the Office Deployment Tool, it is in the configuration file as OfficeClientEdition="64" or "32", see Install Office Professional Plus.
Activate Office as usual.

Typical cases

New PC with 16 GB of memory. Leave the default of 64-bit as it is.

Accounting with an old Excel add-in. The add-in is only available for 32-bit, and the vendor offers no new version. Install 32-bit Office, even if Windows runs as 64-bit.

Access application as .accde from a service provider. Ask which version the file was created with. Which Access you install depends on that.

Visio 32-bit is already installed, and now Office is added. Office is also installed as 32-bit. If you want 64-bit, first uninstall Visio and then install both as 64-bit.

Office at VivaKeys

You choose the bit version during installation, not when you buy. Current editions:
Office Home 2024,
Office Home & Business 2024 and
Office Professional Plus 2024. All offers are in the Microsoft Office category, the overview in the
comparison of the Office 2024 editions. The other technical requirements of the LTSC editions are covered in
Office LTSC 2024 explained.

Frequently asked questions

Is Office 2024 Professional Plus available as a 64-bit download? Yes. Office LTSC Professional Plus 2024 is available in 32-bit and 64-bit versions. You set the version during installation; Microsoft recommends 64-bit from 4 GB of memory.

Do I have to decide between 32-bit and 64-bit when buying? No. According to Microsoft, Office 2024 and Office LTSC 2024 are available in both versions; which one is installed, you set during installation.

Can I install 32-bit and 64-bit Office side by side? No. All Office programs on one device must have the same version. Before a switch, you uninstall the existing installation.

Do my Excel macros also run with 64-bit? Most do. According to Microsoft, only VBA code that calls Windows functions via Declare statements with 32-bit data types has to be adapted.

Is 64-bit Office faster? Not as a general rule. According to Microsoft, it brings advantages with large amounts of data, many add-ins and very large media files.

Sources

Checked on 2026-11-10 against the publisher’s information:

Office 32-bit or 64-bit: which version you should install