Estimation in English: Meaning and How to Use It

What does estimation in English really mean, and how can you use it naturally in speaking and writing? This article provides a full explanation of its meaning, common usage examples, and practical tips for English learners at all levels—from beginner to advanced.

I. What Does Estimation in English?

In English, “estimation” refers to an approximate calculation or judgment about a value, number, quantity, or outcome when exact data is not available. According to the Oxford Dictionary, estimation is “a judgment or opinion about the value or quality of somebody/something.” The Cambridge Dictionary defines it as “a guess of what a size, value, amount, cost, etc. might be.”

Estimation is commonly used in both everyday and academic English, especially in situations where precise figures are not required or not possible to obtain. 

For example:

• “The repair will cost around $200, but that’s just an estimation.”
• “In my estimation, the team will finish the project in two weeks.”

In formal contexts like IELTS, TOEFL, or business writing, estimation helps describe trends, comparisons, or projected outcomes when exact data is missing or unclear. Learners are encouraged to use estimation language in:

• IELTS Writing Task 1, where charts or graphs may not show exact numbers
• Listening or speaking tasks that involve discussing predictions or approximations

II. Ways to Express Estimation in English Communication

When exact numbers are unavailable or unnecessary, English speakers often rely on estimation to communicate effectively. Estimation can be expressed both before and after numerical values, using a range of adverbs, phrases, and structures. These expressions are especially useful in academic writing, casual conversation, and standardized tests like IELTS or TOEFL.

1. Expressions used before numbers

There are several common expressions in English that are placed before numbers to show that the value is an approximation, not an exact figure. These are especially useful in writing or speaking when exact data is unavailable or unnecessary.

These expressions help you write or speak more naturally and accurately, especially when absolute precision is not required—or when the data is unclear. In IELTS Writing Task 1, using such phrases shows flexibility in language and an understanding of how to describe data realistically.

2. Expressions used after numbers

In English, estimation can also be expressed by placing certain words or structures after the number. These expressions are especially common in spoken English, but many are also found in informal writing and everyday communication.

While some of these may not be suitable for academic or formal writing (like the IELTS Writing test), they are useful to know for fluency and naturalness in speech.

III. How to Use Estimation in English for IELTS Writing Task 1

In IELTS Writing Task 1, especially with graphs, charts, and diagrams, you are often expected to describe data that is not presented in exact numbers or that may require rounded or approximate descriptions. In such cases, knowing how to express estimation helps you report trends naturally, avoid repetition, and demonstrate a flexible range of vocabulary.

In some IELTS Writing Task 1 questions, exact figures may not line up neatly, or several categories may contain similar values. Here are examples when estimation is appropriate:

• When the graph does not show exact points, only general shapes or trends
  Example: About 40% of people preferred option A, while roughly one-third chose option B.

• When summarizing a range of years or values
  Example: Sales increased by approximately 15% between 2010 and 2014.

• When describing values that appear similar or close in height
  Example: Both categories reached around 8 million units by the end of the period.

Below are some estimation phrases commonly accepted in Task 1 (formal and academic in tone):

Note: Avoid informal alternatives such as "or so", "ish", or "or something", which are not appropriate for academic writing.

Sample writing paragraph applying estimation:

The bar chart compares the number of hours spent on household tasks by men and women in a typical week. Overall, women carried out significantly more household responsibilities than men.

In detail, females spent around 18 hours per week on housework such as cleaning and cooking, while males did approximately half that amount. Regarding childcare, women dedicated just under 10 hours, compared to roughly 6 hours for men. Leisure activities took up close to 12 hours for both genders. 

Analysis: In this paragraph, various estimation expressions are used to avoid excessive repetition and to handle inexact visual data appropriately.

IV. Using Estimation in English in Business and Everyday Life

Estimation is not only used in academic and exam settings like IELTS, but also plays a vital role in real-world communication.

Estimation in Business English

In professional communication—especially in meetings, emails, reports, and proposals—estimation is often more appropriate than giving exact numbers. This helps avoid overpromising and leaves room for revision or uncertainty when precision is not possible.

Estimation in Everyday English

In informal conversations, English speakers use estimation to sound relaxed and friendly. Unlike business English, estimates in daily life are often less precise and use more colloquial or idiomatic expressions.