Used and loved by millions
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
a third of the time
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "a third of the time" is correct and usable in written English.
You can use it to describe a situation where a certain action or event takes place one-third of the time. For example, "I spend a third of the time in my office, a third of the time working from home, and a third of the time traveling for work."
✓ Grammatically correct
News & Media
Academia
Science
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
60 human-written examples
That is a third of the time.
Then, a third of the time.
News & Media
Biden does so about a third of the time.
News & Media
(Hatch says it's about a third of the time).
News & Media
But let's say it works a third of the time would be good, to some degree.
Academia
And about a third of the time, the author was one of the top 20 guesses.
Academia
He now finishes reports in a third of the time they used to require.
News & Media
He has become acclimated to third in a third of the time that Ripken expected.
News & Media
Favorites win only a third of the time, an immutable racing statistic.
News & Media
(Among the Spanish students, benign envy was described around a third of the time).
News & Media
Those identifications are wrong about a third of the time, studies suggest.
News & Media
Expert writing Tips
Best practice
For clarity, specify the context when using "a third of the time". For instance, instead of just saying "It rains a third of the time", specify "It rains a third of the time during the monsoon season".
Common error
Don't assume "a third of the time" implies predictability. Just because something occurs a third of the time doesn't mean it will happen predictably every third instance. Probability doesn't guarantee regularity.
Source & Trust
92%
Authority and reliability
4.8/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "a third of the time" functions as an adverbial phrase of frequency, modifying a verb or clause to indicate how often an action occurs. According to Ludwig AI, this phrase is correct and usable in written English.
Frequent in
News & Media
69%
Academia
17%
Science
8%
Less common in
Formal & Business
3%
Encyclopedias
0%
Wiki
0%
Ludwig's WRAP-UP
In summary, the phrase "a third of the time" is a common and grammatically correct way to express that something happens approximately 33% of the time. Ludwig AI confirms its usability. While versatile, it's best to provide context for clarity, and avoid assuming the frequency implies predictability. It appears most frequently in news and media, with strong usage in academia, according to Ludwig's analysis. For formal or scientific contexts, more precise statistical language might be preferred.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
one third of the time
Simply replaces "a" with "one", maintaining the same meaning.
33 percent of the time
Expresses the same proportion using a percentage.
once every three times
Describes the frequency as an event happening in a cycle of three.
on one out of three occasions
Similar to the previous phrase but emphasizes specific occasions.
a fraction of the time
Implies a small, unspecified proportion of the time.
some of the time
Indicates that something happens occasionally but doesn't specify the exact frequency.
part of the time
Similar to "some of the time", indicating non-continuous occurrence.
now and then
Suggests that an event happens from time to time.
occasionally
A single-word adverb expressing that something occurs at intervals.
sometimes
A general term for indicating that something happens but without specifying frequency.
FAQs
How can I use "a third of the time" in a sentence?
You can use "a third of the time" to indicate that something occurs in approximately 33% of instances. For example, "I work from home "a third of the time"."
What is a similar phrase to "a third of the time"?
Similar phrases include "one third of the time", "33 percent of the time", or "once every three times". The best choice depends on the specific nuance you want to convey.
Is it more accurate to say "one third of the time" or "a third of the time"?
Both phrases are grammatically correct and widely used. "A third of the time" is slightly more informal, while "one third of the time" is often perceived as more precise, though the meaning remains largely the same.
Does "a third of the time" imply a consistent pattern?
"A third of the time" simply indicates the frequency of an event. It does not necessarily mean the event occurs in a regular or predictable pattern. It just means that, overall, the event happens in approximately one out of every three instances.
Editing plus AI, all in one place.
Stop switching between tools. Your AI writing partner for everything—polishing proposals, crafting emails, finding the right tone.
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
92%
Authority and reliability
4.8/5
Expert rating
Real-world application tested