When choosing between “based on” and “based off of,” the safest and most widely accepted choice is “based on.” It is standard English and works naturally in both formal and informal writing. “Based off of” is also used, especially in American informal speech, but many speakers and editors consider it less standard or unnecessarily wordy.
The two expressions usually communicate the same basic idea: something is developed, created, decided, or influenced by another thing. However, their usage and level of formality are different. If you are writing an essay, email, report, academic assignment, or professional document, “based on” is generally the better choice. In casual conversation, you may hear “based off of” fairly often.
Quick Answer
“Based on” is the standard and preferred expression. “Based off of” is commonly heard in informal American English but is often considered less formal. For school, academic, business, and professional writing, use “based on.” Both expressions can mean that something is developed or determined from another source.
Why Do People Confuse “Based On” and “Based Off Of”?
The confusion happens because both expressions can describe a relationship between an idea, decision, creation, or result and the thing that influenced it.
For example:
- The movie is based on a true story.
- The movie is based off of a true story.
The meaning is easy to understand in both sentences. However, the first version is more conventional and is the better choice in formal writing.
Another reason for the confusion is that English frequently uses on and off to describe relationships. We say things such as “depend on,” “build on,” “work off,” and “draw from.” As a result, speakers sometimes use “based off of” as an alternative to “based on.”
What Does “Based On” Mean?
“Based on” means that something is developed, created, formed, or determined using another thing as its source, evidence, model, or foundation.
It is the traditional and widely accepted expression.
Examples
- The novel is based on real events.
- Her decision was based on the available evidence.
- The film is based on a popular book.
- We made the plan based on customer feedback.
- His opinion is based on personal experience.
Here, on introduces the source or foundation of the idea, decision, or creation.
Is “Based On” Formal?
Yes. “Based on” is appropriate in virtually every type of English writing.
You can use it in:
- Academic writing
- Business writing
- Formal emails
- News writing
- Reports
- Essays
- Everyday conversation
- Creative writing
For example:
The researchers reached their conclusion based on the available data.
This sounds natural and professional.
What Does “Based Off Of” Mean?
“Based off of” is an expression used to mean essentially the same thing as “based on.” It is particularly common in informal American English.
For example:
The character was based off of a real person.
The sentence is understandable, and many native speakers use this expression. However, it is generally less formal than “based on.”
Some speakers and style-conscious editors consider “based off of” nonstandard, awkward, or unnecessarily long. Because of this variation in acceptance, “based on” is the safer choice when you want your English to sound polished and widely acceptable.
Is “Based Off Of” Wrong?
Not necessarily. It is widely used and easily understood, particularly in informal American English. However, it is not the preferred expression in many formal contexts.
If you are unsure, simply use “based on.”
For example:
- Less formal: The show is based off of a comic book.
- Standard: The show is based on a comic book.
The second sentence is a safer choice for formal and international English.
Based On vs Based Off Of: Comparison Table
| Expression | Meaning | Commonness | Formal Writing | Best Choice |
|---|---|---|---|---|
| based on | Developed or determined from something | Very common | Yes | Yes |
| based off of | Developed or determined from something | Common in informal American English | Less preferred | Usually no |
| based upon | Developed or determined from something | Common but somewhat formal | Yes | Yes, when appropriate |
When Should You Use “Based On”?
Use “based on” when something comes from, depends on, or is developed from another source.
1. For books and movies
- The movie is based on a bestselling novel.
- The series is based on historical events.
- The character is based on a real person.
2. For decisions
- The decision was based on the evidence.
- We chose the winner based on performance.
- Her recommendation was based on experience.
3. For research
- The study is based on recent data.
- The conclusion is based on several experiments.
- The report is based on interviews with students.
4. For opinions
- His opinion is based on personal experience.
- My answer is based on the information available.
- Her criticism was based on several observations.
5. For predictions
- The forecast is based on current weather conditions.
- The prediction is based on historical patterns.
- The estimate is based on previous results.
When Can You Use “Based Off Of”?
You may hear or use “based off of” in casual speech, especially in American English.
For example:
- The character was based off of his grandfather.
- The design was based off of an older model.
- The game was based off of a popular TV show.
These sentences are understandable, but “based on” would normally be preferred in polished writing:
- The character was based on his grandfather.
- The design was based on an older model.
- The game was based on a popular TV show.
A useful rule is:
If you are writing for school, work, publication, or an international audience, choose “based on.”
Based On vs Based Off Of: 12 Examples
Here are practical examples showing how the expressions compare.
Example 1: Movie
Standard:
The movie is based on a true story.
Informal alternative:
The movie is based off of a true story.
Example 2: Novel
The television series is based on a popular novel.
The television series is based off of a popular novel.
The first version is more appropriate for formal writing.
Example 3: Decision
Our decision was based on the available evidence.
“Based on” is the natural choice here.
Example 4: Character
The character is based on the author’s childhood friend.
You may hear “based off of” in casual speech, but “based on” is more conventional.
Example 5: Research
The report is based on data collected over five years.
This is the preferred form in academic and professional writing.
Example 6: Design
The new building design was based on traditional architecture.
Example 7: Personal Experience
Her advice was based on personal experience.
Example 8: Historical Events
The novel is based on events that happened during the war.
Example 9: Customer Feedback
The company’s new product was based on customer feedback.
Example 10: Evidence
The conclusion was based on strong evidence.
Example 11: Original Model
The new car was based on an older model.
Example 12: Adaptation
The play is based on a famous Shakespearean work.
In all these examples, “based on” is the most broadly accepted choice.
Common Mistakes With “Based On” and “Based Off Of”
Mistake 1: Using “based off of” in formal writing
Some people write:
The report was based off of recent research.
A more polished version is:
The report was based on recent research.
Mistake 2: Assuming “based off of” is always incorrect
It is better not to say that every use of “based off of” is simply wrong. The expression is established in informal usage, particularly in American English.
The important distinction is standard/formal usage versus informal usage.
Mistake 3: Adding unnecessary words
“Based off of” contains more words than “based on” without normally adding a different meaning.
Compare:
- Based on the evidence
- Based off of the evidence
The first is shorter and more conventional.
Mistake 4: Using the wrong preposition
Avoid changing the expression to forms such as:
- based at
- based by
- based from
when you mean that something was developed from a source.
For this meaning, based on is the standard construction.
A Simple Memory Trick
Remember this:
A foundation is something you build ON.
So:
Based ON = built or developed ON a foundation.
Think of a house. A house is built on a foundation. In the same way, an idea, decision, movie, or conclusion can be based on something.
You can also remember:
When in doubt, use “based on.”
It is short, natural, and widely accepted.
American vs British English
There is an important usage difference to keep in mind.
“Based on” is standard in both American and British English. It is the safest expression for speakers and writers regardless of location.
“Based off of” is especially associated with informal American English. It is also understood elsewhere, but it is less likely to be the preferred choice in formal British English.
For international communication, “based on” is therefore the clearest option.
For example:
- American English: The film is based on a novel.
- British English: The film is based on a novel.
The standard expression remains the same.
Similar Words and Expressions
Several expressions are related to “based on.” Understanding them can make your writing more flexible.
Based upon
“Based upon” has essentially the same meaning as “based on.” It can sound slightly more formal or traditional.
The decision was based upon the available evidence.
In most everyday situations, “based on” is simpler.
Derived from
“Derived from” means that something originates from another source.
The word is derived from Latin.
This is not always interchangeable with “based on.”
Inspired by
“Inspired by” means that something influenced an idea or creation.
The artist created the painting inspired by nature.
An inspiration does not necessarily provide the complete foundation of something.
According to
“According to” introduces information attributed to a person, source, or authority.
According to the report, sales increased.
It does not have the same meaning as “based on.”
Depending on
“Depending on” means that something changes according to a particular condition.
The price varies depending on the season.
Again, this is related to the idea of conditions or factors but is not a direct replacement for “based on.”
Final Verdict
When deciding between “based on” and “based off of,” use “based on” as your default.
“Based on” is standard, concise, widely accepted, and suitable for both formal and informal English. “Based off of” is commonly used in informal American English, but it can sound less polished and may be discouraged by some editors or teachers.
If your goal is clear, professional, and broadly accepted English, the simple rule is:
Use “based on.”
Frequently Asked Questions
Is “based off of” grammatically correct?
“Based off of” is widely used and understood, particularly in informal American English. However, it is less universally accepted than “based on,” so “based on” is generally preferable in formal writing.
Is “based on” or “based off of” better?
“Based on” is the safer and more standard choice. It works naturally in academic, professional, formal, and everyday English.
Is “based off of” American English?
It is strongly associated with informal American English. It can be heard in everyday conversation, although many American speakers and editors still prefer the traditional “based on.”
Can I use “based off of” in an essay?
It is better to use “based on” in an academic essay. This avoids questions about formality and follows the more widely accepted construction.
Is “based upon” correct?
Yes. “Based upon” is correct and has essentially the same meaning as “based on.” It can sound somewhat more formal or traditional.
Which is correct: “based on a true story” or “based off of a true story”?
“Based on a true story” is the standard and preferred expression. “Based off of a true story” is used informally, but “based on” is the safer choice.
Does “based off of” mean something different from “based on”?
Usually, no. Both expressions generally mean that something was developed, created, or determined from another source. The main difference is usage and level of formality.
Remember This
- Based on = standard and widely accepted.
- Based off of = informal expression, especially common in American English.
- Based upon = correct, with a somewhat formal or traditional tone.
- For school and professional writing, choose based on.
- When you are unsure, based on is the safest choice.
Conclusion
“Based on” and “based off of” can communicate the same basic idea, but they do not have the same level of acceptance in every context. “Based on” is the conventional expression and is appropriate in formal, academic, professional, and everyday English. “Based off of” is common in informal speech, particularly in American English, but some speakers and editors consider it less standard.
For learners of English, the easiest rule is also the most useful one: choose “based on” when you want clear, natural, and widely accepted English. Once you recognize this pattern, you can confidently describe movies, books, decisions, research, opinions, designs, and conclusions without worrying about which expression to choose.
