Trimmed Mean Calculator

Calculate a trimmed mean by removing the same percentage of low and high values before averaging

Calculate a trimmed mean for a numeric dataset.

A trimmed mean sorts the dataset, removes the same percentage of values from the low and high ends, then averages the remaining values.

Use it when outliers should be excluded rather than capped, such as survey scores, judging panels, quality metrics, and noisy measurements.

Example Results

1 examples

Trim outliers before averaging

Remove one low and one high value before calculating the mean.

{
  "result": {
    "trimmedMean": 15
  }
}
View input parameters
{ "dataset": "10, 12, 14, 16, 18, 100", "trimPercent": 20, "decimalPlaces": 2, "includeTrimmedValues": true }

Key Facts

Category
Math, Date & Finance
Input Types
textarea, number, checkbox
Output Type
json
Sample Coverage
4
API Ready
Yes

Overview

The Trimmed Mean Calculator provides a robust way to find the average of a numeric dataset by excluding extreme outliers. By sorting your data and removing a specified percentage of the highest and lowest values, it calculates a more accurate central tendency that is not skewed by anomalies or measurement errors.

When to Use

  • •When analyzing survey scores or judging panel results where extreme bias might exist.
  • •When processing noisy sensor data or quality metrics that occasionally produce false spikes.
  • •When you need a robust statistical average that completely excludes outliers rather than just capping them.

How It Works

  • •Enter your numeric dataset as a comma-separated list in the input field.
  • •Specify the percentage of values to trim from each tail (e.g., 10% from the top and 10% from the bottom).
  • •The tool sorts the numbers, removes the specified outliers, and calculates the mean of the remaining values.

Use Cases

Calculating final scores in competitive judging by dropping the highest and lowest judge scores.
Evaluating average employee salaries or real estate prices without the distortion of extreme high or low figures.
Filtering out temporary sensor malfunctions when calculating average daily temperatures or machine performance metrics.

Examples

1. Calculating a fair competition score

Event Judge
Background
A gymnastics competition uses 10 judges, but occasionally one judge gives an unusually harsh or generous score.
Problem
Calculate a fair average score by dropping the highest and lowest scores to prevent bias.
How to Use
Enter the 10 scores into the dataset field and set the trim percentage to 10%.
Example Config
{"dataset": "8.5, 8.7, 8.8, 8.9, 9.0, 9.1, 9.1, 9.2, 9.3, 10.0", "trimPercent": 10, "decimalPlaces": 2}
Outcome
The 8.5 (lowest) and 10.0 (highest) scores are removed, and the remaining 8 scores are averaged for a fair final result.

2. Analyzing average property prices

Real Estate Analyst
Background
A neighborhood has mostly mid-range homes, but one massive mansion and one dilapidated property skew the standard average.
Problem
Find the typical home price without the extreme outliers distorting the data.
How to Use
Paste the list of recent sale prices and apply a 15% trim to both tails.
Example Config
{"dataset": "50000, 310000, 315000, 320000, 325000, 330000, 340000, 2500000", "trimPercent": 15, "decimalPlaces": 0}
Outcome
The tool drops the $50,000 and $2,500,000 properties, returning a trimmed mean that accurately reflects the standard market value.

Try with Samples

video, barcode
Duplicate Line Samples
Sample files with various types of duplicate lines for testing duplicate removal tools
matched family video
video
Special Characters Samples
Sample text files with various special characters, punctuation, and symbols for testing non-alphanumeric character removal
matched family video
video
Code Comment Samples
Sample code files with various comment styles for testing comment removal
matched family video
video
Regex Replace Samples
Collection of common and useful regex replacement patterns for text transformation and data cleaning
matched family video
video

Related Hubs

Video-to-Audio and Animation Conversion Tools
Compare tools that turn video into audio, extract video streams, and convert between short-form video and animated image formats in one hub.
Video Preview, Extraction, and Subtitle Tools
Compare video preview generation, stream extraction, audio extraction, subtitle translation, and quick flip tools in one hub for lightweight video prep workflows.
Barcode, QR Code, and Label Tools
Compare barcode generation, QR code creation and decoding, UPC/EAN validation, WiFi QR sharing, and printable label tools in one hub.

FAQ

What is a trimmed mean?

A trimmed mean is a method of averaging that removes a small, specified percentage of the largest and smallest values before calculating the mean, reducing the impact of outliers.

How is the trim percentage applied?

The percentage applies to each tail. For example, a 10% trim on a dataset of 100 items will remove the 10 lowest and 10 highest values.

What is the maximum trim percentage allowed?

You can trim up to 45% from each tail. Trimming 50% from both ends would leave no data to average.

Can I see which values were removed?

Yes, by enabling the 'Include Trimmed Values' option, the output will display the specific numbers that were excluded from the final calculation.

How does this differ from Winsorizing?

A trimmed mean completely removes the extreme values from the dataset, whereas Winsorizing replaces those extreme values with the nearest remaining values before averaging.

API Documentation

Request Endpoint

POST /en/api/tools/trimmed-mean-calculator

Request Parameters

Parameter Name Type Required Description
dataset textarea Yes -
trimPercent number No -
decimalPlaces number No -
includeTrimmedValues checkbox No -

Response Format

{
  "key": {...},
  "metadata": {
    "key": "value"
  },
  "error": "Error message (optional)",
  "message": "Notification message (optional)"
}
JSON Data: JSON Data

AI MCP Documentation

Add this tool to your MCP server configuration: 

{
  "mcpServers": {
    "elysiatools-trimmed-mean-calculator": {
      "name": "trimmed-mean-calculator",
      "description": "Calculate a trimmed mean by removing the same percentage of low and high values before averaging",
      "baseUrl": "https://elysiatools.com/mcp/sse?toolId=trimmed-mean-calculator",
      "command": "",
      "args": [],
      "env": {},
      "isActive": true,
      "type": "sse"
    }
  }
}

You can chain multiple tools, e.g.: `https://elysiatools.com/mcp/sse?toolId=png-to-webp,jpg-to-webp,gif-to-webp`, max 20 tools.

If you encounter any issues, please contact us at [email protected]