Free Size Converter: US, UK, EU & International Sizes
Convert bra, shoe, clothing, ring, belt, hat, glove, helmet, bedding, bike and wetsuit sizes with private, mobile-friendly tools that open instantly and require no signup.
Accurate
Charts are built from standard international sizing references.
No signup
Every converter opens instantly with no account or email gate.
Mobile-ready
Large inputs and clear results work cleanly on any device.
What Size Convertly does
Size Convertly helps shoppers compare sizes across US, UK, EU, FR/ES, Italian, Japanese, centimeter and inch-based sizing systems. Instead of searching through separate charts, pick a focused converter, enter the size you know, and use the chart and measuring notes to choose the closest equivalent.
The tools cover everyday sizing questions for fashion, jewelry, accessories, sports gear and home bedding. Because brand fit can vary, every result is a practical starting point and should be checked against the brand's own fit guide when available.
Popular Conversions
Jump straight into the most common sizing questions.
Browse by category
Start with the type of product you are measuring, then open the converter with the matching regional standards.
Clothing & Body
Bras, clothing, kids sizes, suits and underbust band conversions.
Accessories
Shoes, rings, belts, hats, gloves, watches, sunglasses and chains.
Sports & Gear
Helmet, bike frame and wetsuit size lookups from body measurements.
Home & Bedding
Mattress, bed and pillow dimensions across US, UK and EU labels.
Pick a converter
Eighteen focused tools cover clothing, shoes, rings, bras, accessories, sports gear, bikes, and bedding sizes.
Shoe Size Converter
Convert shoe sizes between US, UK, EU, CM, and JP.
ConverterTry nowRing Size Converter
Convert ring sizes between US, UK, EU, and mm.
ConverterTry nowClothing Size Converter
Convert clothing sizes between US, UK, and EU.
ConverterTry nowBra Size Converter
Convert bra sizes across US, UK, EU, FR/ES, and IT.
ConverterTry nowBelt Size Converter
Convert waist measurements to belt size labels.
ConverterTry nowHat/Cap Size Converter
Convert hat sizes between US, UK, EU, and head circumference.
ConverterTry nowGlove Size Converter
Convert glove sizes between US, UK, EU, and hand circumference.
ConverterTry nowKids Clothing & Shoe Size Converter
Find clothing and shoe sizes by age, height, and weight.
ConverterTry nowWatch Band Size Converter
Match wrist circumference to common watch band lengths and labels.
ConverterTry nowNecklace/Chain Length Guide
Convert chain lengths between inches and centimeters by style.
ConverterTry nowBike Frame Size Converter
Find road, mountain, and hybrid bike frame sizes from height.
ConverterTry nowSuit/Blazer Size Converter
Convert chest measurements to US, UK, EU, and alpha jacket sizes.
ConverterTry nowBra Band-to-Underbust Converter
Convert underbust measurements to bra band labels by region.
ConverterTry nowSunglasses Frame Size Converter
Compare face width with lens, bridge, temple, and frame sizes.
ConverterTry nowHelmet Size Converter
Convert head circumference to bike and ski helmet sizes.
ConverterTry nowWetsuit Size Converter
Compare wetsuit sizes by height, weight, chest, and metric ranges.
ConverterTry nowMattress/Bed Size Converter
Compare US, UK, and EU bed dimensions in inches and centimeters.
ConverterTry nowPillow Size Converter
Convert common pillow dimensions across US, UK, and EU bedding.
ConverterTry now