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
for which period
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "for which period" is correct and usable in written English.
You can use it in a sentence to indicate a specific amount of time. For example: Please provide details regarding the rental, for which period we are discussing.
✓ Grammatically correct
Science
News & Media
Alternative expressions(20)
period for which
during which timeframe
over what duration
for what length of time
in what time frame
through which duration
spanning what interval
for which term
for which moment
for which stage
for which order
for which expiration
for which half
for which peak
for which timeframe
for which month
for which leadership
for which age
for which completion
for which item
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
4 human-written examples
A further important issue is for which period exposure is characterized.
Additionally, subjects will briefly report their activities as well as for which period during the day the accelerometer is worn.
Science
Our detector was applicable to the three experiments for which period times were reported: α-factor synchronization (18 time points), cdc15 synchronization (24 time points) and cdc28 synchronization (17 time points).
Science
Table 2 contains some highlights for the three GGS countries for which period survival tables are available, 5 and we see that there was considerable cohabitation already around the late 1980s and that in Bulgaria and Russia, it had outflanked direct marriage at least by the early 21st century.
Human-verified similar examples from authoritative sources
Similar Expressions
56 human-written examples
For which periods and places and aspects of the past is data readily available?
News & Media
"The next few years will be a very exciting time for McLaren, during which period we intend to become an ever-stronger technological and economic force".
News & Media
The percentage of instances for which each period estimation method correctly predicted the period-10 behaviour was then recorded.
Science
The period of observation was from 1972 to 1995 (except for Okinawa, for which the period was from 1973 to 1995).
Science
Assessment was retrospective and covered a period of 3 months, except for in patient treatment and nursinghome care, for which the period was 6 months.
Science
In the special case for which for some period, the system becomes the linear periodically time-variant (LPTV).
From the value perspective, they would seek an affordable cost (initial and ongoing) for which the payback period is short.
Science
Expert writing Tips
Best practice
When using "for which period", ensure the context clearly defines what "period" refers to. Avoid ambiguity by specifying units of time (e.g., days, months, years).
Common error
Avoid using "for which period" without clearly defining the period in question. Instead of saying "data for which period is unavailable", specify the exact timeframe: "data for the 2010-2015 period is unavailable".
Source & Trust
88%
Authority and reliability
4.1/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "for which period" functions as a relative phrase, introducing a clause that modifies a noun related to time. According to Ludwig AI, this phrase is grammatically sound and suitable for use in written English.
Frequent in
Science
60%
News & Media
30%
Formal & Business
10%
Less common in
Encyclopedias
0%
Wiki
0%
Reference
0%
Ludwig's WRAP-UP
In summary, "for which period" is a grammatically correct phrase used to specify a timeframe, commonly appearing in science and news contexts. While relatively rare, according to Ludwig AI the phrase is considered correct, ensure its usage adds clarity by explicitly defining the "period" being referenced. Alternative phrases like "during which timeframe" or "over what duration" can offer similar meaning with slight differences in nuance. This phrase is well-suited for formal writing where precision and clarity are essential.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
during which timeframe
Focuses on a specific duration or span of time.
over what duration
Emphasizes the length of time something occurs.
for what length of time
Highlights the measurement of the duration.
in what time frame
Similar to timeframe, but slightly more informal.
through which duration
Suggests a process or experience that lasts for a certain time.
spanning what interval
More formal and emphasizes the start and end points.
throughout which span
Highlights a broad duration.
covering which term
Implies something that is encompassed or included within the time.
within which phase
Highlights particular stage.
across what timeline
Emphasizes a chronological sequence of events.
FAQs
How can I use "for which period" in a sentence?
You can use "for which period" to specify a timeframe related to a particular event or data. For example, "The study analyzed the data for 1990-2000, the "period for which" the data are most reliable."
What are some alternatives to "for which period"?
Alternatives include "during which timeframe", "over what duration", or "in what time frame". Each alternative provides a slightly different nuance, so choose the one that best fits the context.
Which is more formal, "for which period" or "during which time"?
"For which period" is generally considered more formal. "During which time" may be more appropriate for less formal contexts.
Is "for which period" interchangeable with "during which period"?
While similar, "for which period" often implies a reason or condition related to the period, whereas "during which period" simply indicates when something occurred. They can be interchangeable in many cases but not all.
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
88%
Authority and reliability
4.1/5
Expert rating
Real-world application tested