Free Online Utility Tools
A comprehensive collection of daily-use utilities designed for accuracy and privacy. From health metrics to technical data conversions, our tools are built to run entirely in your browser for a safe and seamless experience.
Age Calculator
Find your exact age in years, months and days from any date.
Find Age 🚀BMI Calculator
Calculate your Body Mass Index and healthy weight range instantly.
Check BMI ⚖️Unit Converter
Convert length, weight, temperature, speed and volume units with precision.
Convert 📏Date Difference
Calculate the exact number of days, weeks, and months between two dates.
Calculate Duration 📅IMEI Validator
Verify any 15-digit mobile IMEI number using the industry-standard Luhn algorithm.
Validate IMEI 🔍Battery Life
Estimate device battery runtime based on capacity and current consumption.
Estimate 🔋Data Converter
Convert between KB, MB, GB and TB data storage units accurately.
Convert Data 📡Storage Calculator
Estimate how many photos, songs, or videos fit on any storage drive.
Plan Storage 📦JSON Formatter
Format, validate, and minify JSON strings with instant syntax checks.
Format JSON 💻Base64 Encoder
Convert plain text or files to Base64 format or decode back locally.
Convert Base64 🔣UUID Generator
Generate single or batch cryptographically secure random UUID v4s.
Generate UUID 🆔Regex Tester
Test, validate, and debug regular expression matches and capture groups.
Test Regex 🧪Meta Tag Generator
Create search-engine friendly title, description, and social meta tags.
Generate Tags 🏷️Robots.txt Generator
Generate robots.txt crawl configurations to guide search engine spiders.
Generate Robots 🤖Sitemap Generator
Generate search engine compliant sitemaps from list of pages.
Generate Sitemap 🗺️Schema Generator
Generate FAQ, Article, Product, and Local Business JSON-LD schema markup.
Generate Schema 🗂️Color Palette Generator
Generate harmonic, monochromatic, or triad palettes and copy colors.
Generate Palette 🎨CSS Gradient Generator
Design beautiful linear or radial CSS gradients with multi-stop handles.
Create Gradient 🌈The technology behind browser-based calculations
Daily tasks like converting units, checking health indices, and validating device numbers often require simple calculations. Historically, these calculations were handled by server-side scripts. However, modern web standards allow browsers to run these calculations locally.
By running calculations directly in your browser, OrangeTool ensures your personal data (such as health metrics, age details, and device IMEI numbers) remains private. No data is sent over the network, providing security for your personal information.
Deep dive: Our utility calculators
1. BMI Calculator
The Body Mass Index (BMI) calculator uses the standard WHO formula:
BMI = weight (kg) / height^2 (m^2). It supports both metric and imperial units and categorizes the results into standard health ranges (underweight, normal weight, overweight, obese).
2. IMEI Validator
The IMEI Validator checks the 15-digit International Mobile Equipment Identity (IMEI) number using the Luhn algorithm. It calculates the check digit by doubling every second digit and summing the results, verifying that the input number matches standard specifications.
3. Unit Converter
The Unit Converter handles conversions for length, weight, area, volume, and temperature. It applies high-precision conversion factors locally, providing quick and accurate conversions without network latency.
4. Age & Date Difference Calculators
The Age and Date calculators use browser date functions to calculate durations between dates. They handle leap years and month lengths, providing results in years, months, weeks, and days.
World Health Organization (WHO) BMI Classifications
Standard weight categories and risk profiles for adults:
| BMI Range | Classification | Health Risk Profile | Recomendation |
|---|---|---|---|
| Below 18.5 | Underweight | Nutritional deficiency risks | Consult a healthcare provider |
| 18.5 - 24.9 | Normal Weight | Low risk profile | Maintain current balanced diet and exercise |
| 25.0 - 29.9 | Overweight | Moderate risk profile | Monitor diet and increase physical activity |
| 30.0 and Above | Obese | High risk profile (cardiovascular, diabetes) | Consult a healthcare professional |
Frequently Asked Questions
Does the BMI calculator factor in muscle mass or frame size?
No. BMI is a general ratio of weight to height and does not distinguish between muscle, bone density, or body fat. It is a helpful general guide but has limitations for athletes and bodybuilders.
How secure is the IMEI validator?
The IMEI validator checks the 15-digit number locally in your browser. No data is sent over the network, keeping your device identification details private.
Can the unit converter handle non-standard conversions?
The tool supports standard conversions for length, weight, area, volume, and temperature. For specialized technical conversions, you can check our reference guides.
How do you calculate the duration between two dates?
The tool calculates date differences using browser date functions, factoring in leap years and varying month lengths to provide accurate results.
Does the storage calculator support modern file formats?
Yes. The storage calculator includes averages for modern formats like 12MP photos, 4K video clips, and high-quality MP3 tracks, helping you estimate storage capacity.