Why is spell check so slow in Word?

Real-time spell checking processes every word as you type. In large documents or with multiple proofing languages installed, this can consume significant CPU resources.

Fix: Spell Check Running Very Slowly in Word

Why Spell Check Slows Down

Real-time spell checking is resource-intensive, especially in large documents or when multiple proofing languages are active.

手順

Step 1: Disable Real-Time Spell Check

Go to File > Options > Proofing
Uncheck Check spelling as you type
Uncheck Mark grammar errors as you type
Use F7 to run manual spell check when you’re ready

Step 2: Remove Extra Proofing Languages

Go to File > Options > Language
Under Office authoring languages and proofing, remove languages you don’t use
Restart Word

Step 3: Exclude Sections from Spell Check

For documents with code, foreign text, or technical terms:

Select the section to exclude
Go to Review > Language > Set Proofing Language
Check Do not check spelling or grammar

Step 4: Reset Custom Dictionary

A large custom dictionary can slow spell check:

Go to File > Options > Proofing > Custom Dictionaries
Select the default dictionary and click Edit Word List
Remove unnecessary entries, or click Delete all

Quick Fix

If you need speed right now, switch to Draft view (View > Draft) and disable proofing marks. This gives Word less to render and process simultaneously.