I know that

USAGE SUMMARY

"I know that" is correct and can be used in written English.
You can use this phrase to emphasize a statement or opinion that follows, often to show that the speaker has done their research or is confident in their answer. For example: "I know that the Great Wall of China is the longest man-made structure in the world."

✓ Grammatically correct

News & Media

Science

Formal & Business

Human-verified examples from authoritative sources

Exact Expressions

60 human-written examples

I know that feeling.

The New York Times

"I know that look.

The New York Times

"I know that place.

Independent

Even I know that".

The New Yorker

How do I know that?

The New York Times

"I know that pretty well.

The New Yorker

"I know that sounds cheesy.

The New York Times

"I know that sounds weird.

The New York Times

I know that "veil" is.

The New York Times

"I know that sounds pretentious.

The New York Times - Books

I know that very well.

The New Yorker

Expert writing Tips

Best practice

Use "I know that" to introduce a statement of fact or a well-informed opinion, establishing your credibility or knowledge on the topic.

Common error

Avoid using "I know that" too frequently in casual conversation, as it can sound overly assertive or even condescending. Consider using more conversational alternatives like "I think" or "I believe" in informal settings.

Linguistic Context

The phrase "I know that" functions as a declarative statement, indicating the speaker's awareness or certainty regarding a piece of information. As Ludwig AI states, it emphasizes a statement of fact or well-informed opinion. The examples show how this phrase prefaces various types of information, from simple facts to more complex understandings.

Expression frequency: Very common

Frequent in

News & Media

54%

Science

25%

Formal & Business

8%

Less common in

Wiki

6%

Academia

0%

Reference

0%

Ludwig's WRAP-UP

In summary, the phrase "I know that" is a very common and grammatically correct way to express awareness or certainty. According to Ludwig AI, it's suitable for introducing a fact or well-informed opinion. While versatile, it's important to avoid overuse in informal contexts to prevent sounding overly assertive. As demonstrated by the provided examples, the phrase appears frequently in news, scientific and business contexts. Therefore, it can be safely used across different writing registers.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

I am aware that

A more formal way of expressing knowledge or understanding.

I'm conscious that

Similar to 'I am aware', but can imply a stronger sense of being mindful or noticing something.

It is known to me that

A more detached, slightly more formal way of stating knowledge.

I realize that

Implies a process of coming to understand or acknowledge something.

I understand that

Focuses more on comprehension and acceptance of a piece of information.

I'm certain that

Indicates a high degree of confidence in the knowledge being expressed.

I'm sure that

Similar to 'I'm certain', but can also convey a sense of reassurance.

I have no doubt that

Emphasizes the lack of uncertainty regarding the information.

It's my understanding that

Highlights that the information is based on personal interpretation or information received.

I've been informed that

Indicates that the knowledge comes from an external source.

FAQs

How can I use "I know that" in a sentence?

Use "I know that" to introduce a fact or something you believe to be true, like "I know that the meeting starts at 10 AM" or "I know that this project will be successful".

What can I say instead of "I know that"?

You can use alternatives like "I am aware that", "I understand that", or "I'm certain that" depending on the context.

Which is correct, "I know that" or "I knew that"?

"I know that" is used for present knowledge, while "I knew that" is used for past knowledge. For example, "I know that the Earth is round" versus "I knew that she was coming today".

What's the difference between "I know that" and "I think that"?

"I know that" implies certainty or factual knowledge, while "I think that" expresses an opinion or belief. Use "I know that" when you're confident in your information and "I think that" when you're expressing a personal viewpoint.