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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
knows inside and out
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "knows inside and out" is correct and usable in written English.
It is typically used to describe someone who has a thorough and comprehensive understanding of a subject or topic. Example: "As a seasoned expert in the field, she knows the industry regulations inside and out."
✓ Grammatically correct
News & Media
Wiki
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
Sir Andrew drew some lively playing from the orchestra in Strauss's "Rosenkavalier" Suite, music he knows inside and out from his work in the world's great opera houses.
News & Media
If you're going to play a song that's most likely been number one for 15 weeks and everybody already knows inside and out, why not spice things up a little?
News & Media
MR: Then, of course, there is the title track of the film Against All Odds, a song that I think everybody knows inside and out.
News & Media
When we interviewed Mike Gao, we realized that he understands his gear better than any beat maker around because he makes half the applications himself, and whatever he didn't personally create, he knows inside and out.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
51 human-written examples
But don't jump so quickly at a position you already know inside and out, said Kelly Studer, a San Francisco-based career coach.
News & Media
London was suddenly new and exciting again, and the familiar streets I thought I knew inside and out became strange.
News & Media
In yoga, we talk about "foundational poses," or key asanas to know inside and out and return to regularly -- no matter your level or experience.
News & Media
This was a constantly surprising account of a score I thought I knew inside and out.
News & Media
I see it more as vulnerability, the kind of harm we can come to by being seen and known, inside and out.
News & Media
You can bet that all 75 seconds of this song were known inside and out by early DC bands.
News & Media
Even if the founder has no background in sales, they should be able to pitch and sell this product that they know inside and out.
News & Media
Expert writing Tips
Best practice
Use "knows inside and out" to emphasize a deep and comprehensive understanding, suggesting expertise and familiarity beyond surface-level knowledge.
Common error
Avoid using "knows inside and out" too frequently in your writing. While effective, overuse can make your writing sound repetitive. Instead, vary your language by using synonyms like "has a thorough understanding of" or "is intimately familiar with".
Source & Trust
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "knows inside and out" functions as a verb phrase that describes a state of complete and thorough understanding. As Ludwig AI suggests, the phrase indicates that someone possesses detailed knowledge and familiarity with a particular subject, system, or concept. Examples in Ludwig demonstrate its usage across various contexts, from music to professional expertise.
Frequent in
News & Media
66%
Wiki
23%
Formal & Business
11%
Less common in
Academia
0%
Science
0%
Encyclopedias
0%
Ludwig's WRAP-UP
The phrase "knows inside and out" is a common expression used to describe someone who possesses a very thorough and detailed understanding of a subject or topic. Ludwig AI confirms its grammatical correctness and usability in written English. While not overly formal, it is suitable for various contexts, including news, wiki articles, and professional settings. The phrase emphasizes expertise and a deep level of familiarity. To avoid repetition, consider using alternatives such as "is intimately familiar with" or "has a thorough understanding of". Ludwig's examples illustrate the versatility of this phrase across different domains, reinforcing its value in conveying comprehensive knowledge.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
knows like the back of their hand
Uses an idiom to convey complete familiarity.
has a thorough understanding of
Highlights the completeness and depth of understanding.
has a comprehensive grasp of
Focuses on the ability to understand and handle complex concepts.
is intimately familiar with
Emphasizes a close and personal familiarity.
is deeply acquainted with
Focuses on a profound and personal level of familiarity.
is well-versed in
Indicates extensive knowledge and expertise.
is an expert in
Indicates recognized skill or knowledge in a particular area.
is conversant with
Suggests a knowledgeable and articulate understanding.
has mastered
Emphasizes complete control and understanding.
possesses encyclopedic knowledge of
Highlights vast and comprehensive knowledge.
FAQs
What does "knows inside and out" mean?
The phrase "knows inside and out" means to have a very thorough and detailed understanding of something. It implies a deep familiarity and expertise.
When is it appropriate to use the phrase "knows inside and out"?
It is appropriate to use "knows inside and out" when you want to emphasize that someone has a complete and comprehensive understanding of a subject, skill, or system. It suggests they are very familiar with all aspects of it.
What are some alternatives to saying "knows inside and out"?
Some alternatives include "is intimately familiar with", "has a thorough understanding of", or "knows like the back of their hand" depending on the context.
Is "knows inside and out" formal or informal?
The phrase "knows inside and out" is generally considered informal, but it can be used in neutral contexts. For more formal writing, consider using phrases like "has a comprehensive grasp of".
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
82%
Authority and reliability
4.5/5
Expert rating
Real-world application tested