About SizeFit
SizeFit helps you convert and measure sizes for shoes, clothing, bras, rings, and more—especially when labels differ by country or brand.
We started in 2025 because cross-border shopping often means guessing US, UK, EU, or Asian sizes. These free converters and charts turn a size you know into the one you need—and measurement guides help when the label alone is not enough.
What We Offer
Size Converters
Free converters by product type:
- • Shoe Size Converter - Convert between US, UK, EU, Japanese, and CM measurements for men's, women's, and kids' shoes
- • Clothing Size Converter - Transform clothing sizes across US, UK, EU, and Asian standards
- • Bra Size Calculator - Calculate bra size from band and bust measurements
- • Ring Size Converter - Convert ring sizes between US, UK, EU, and Japanese standards
- • Hat Size Converter - Find your hat size across different international standards
- • Top Size Converter - Match chest, waist, and hip measurements to top sizes
- • Mattress Size Converter - Compare mattress sizes across US, UK, EU, and other regions
Brand-Specific Size Charts
We understand that different brands have different sizing standards. That's why we provide:
- • Brand Shoe Size Comparison - Compare sizes across Nike, Adidas, New Balance, Converse, Vans, and more
- • Official brand size charts based on manufacturer specifications
- • Kids size conversion tools with age and measurement references
- • Men's to women's shoe size conversion for cross-gender shopping
- • Printable measurement tools like our Printable Ring Sizer
Accuracy & Reliability
At SizeFit, accuracy is our top priority. Our size conversion data is based on:
- ✓Official Brand Size Charts: We reference official sizing information from major brands including Nike, Adidas, New Balance, Converse, Vans, and many others.
- ✓International Standards: Our conversions follow recognized international sizing standards (ISO, ASTM, and regional standards).
- ✓Regular Updates: We update charts when brands publish changes and when readers flag outdated sizes.
- ✓Measurement-Based Calculations: Tools prefer real body numbers (chest, waist, hips, foot length) over guessing from a single label.
While we strive for accuracy, we always recommend checking the specific brand's size guide when making a purchase, as sizing can vary between different product lines and styles.
Measurement Guides
Measure at home with these short guides, then use a converter or chart:
How to Measure Shoe Size
Measure foot length and width at home, then match a chart.
Body Measurement Guide
Learn how to measure chest, waist, and hips for clothing sizes.
Bra Size Measurement
Measure band and cup at home, then check sister sizes.
Size Charts Library
Charts for shoes, clothing, bras, rings, and more.
Our Mission
SizeFit exists so cross-border sizing is clearer: convert a size you know, or measure at home when the label alone is not enough.
We're committed to:
- Providing free, clear size converters anyone can use
- Supporting international shoppers by bridging the gap between different sizing systems
- Offering clear measurement guides so you can measure yourself accurately
- Maintaining up-to-date brand size information to reflect real-world sizing variations
- Creating a user-friendly experience that makes size conversion quick and intuitive
Why Choose SizeFit?
Global Coverage
Support for US, UK, EU, Asian, and other international sizing standards. Convert between any combination of systems instantly.
Accurate Conversions
Based on brand size charts and international standards. Treat results as a starting point—brands still vary.
Fast & Free
All our tools are free to use—no registration required. Convert sizes right away.
Get in Touch
Have questions, feedback, or suggestions? We'd love to hear from you! Visit our contact page to reach out, or explore our measurement guides for detailed instructions on how to measure yourself accurately.
Thank you for using SizeFit. We hope these tools make cross-border and brand sizing clearer next time you shop.