Updated iPhone interface
The updated app keeps ring measurement, finger measurement, conversion, and saved sizes cleanly connected.
Measure a ring, measure a finger, convert standards, and save sizes without visiting a jeweler.
Ring Measurement
Place a ring on the circle and adjust the guide until the inner edge matches.
Saved Sizes
Keep important ring sizes ready for yourself, family, partners, and gift planning. Operations Management By William J. Stevenson 13th Edition
Global Size Standards
Convert between US, UK, EU, Japan, Australia, India, and millimeter measurements.
Finger Width Mode
No ring? Measure your finger directly across the on-screen bar and fine-tune the millimeter value. New sections on using Excel and Minitab for
Offline & Private
Works fully offline. Your data never leaves your device. Zero tracking.
Instant Results
Your size appears immediately in all major standards — US, UK, EU, and more. Summary of Contents The 13th edition of Operations
Engagement Ready
Planning a surprise proposal? Secretly measure a ring while they're away.
Size History
Track how your ring size changes over time with measurement history.
Clean iPhone UI
Large controls, clear rulers, and focused sheets make each sizing task easy to follow.
New sections on using Excel and Minitab for statistical process control. The “Operation Analytics” boxes show how data scientists use regression and simulation to solve OM problems.
: Predicting demand to optimize workforce and resource allocation. Summary of Contents
The 13th edition of Operations Management by William J. Stevenson
The builds on this legacy by addressing the most pressing challenges of the 2020s. While previous editions laid the groundwork in Six Sigma and Lean, this iteration introduces updated case studies on post-COVID supply chains, the integration of AI in forecasting, and sustainability as a core operational metric.
Modern operations are no longer just about efficiency; they are about responsibility. This edition places a heavy emphasis on "triple bottom line" thinking—balancing profit, people, and the planet. Readers explore how supply chains can be made more sustainable and the ethical implications of sourcing and production. 2. The Service Economy
The text is designed for ease of learning, featuring "Taking Stock" summaries, "Critical Thinking" exercises, and integrated Connect® digital resources.
No jeweler visit. No guesswork. Just your phone.
Choose a Mode
Measure an existing ring on the circle, or switch to finger width mode when no ring is available.
Align the Guide
Use the ruler, slider, and plus/minus controls to match the ring or finger width precisely.
Save or Convert
See the measurement instantly, save it for later, or convert it between international standards.
Buy jewelry anywhere in the world with confidence.
US
& Canada
UK
& Australia
EU
Europe
JP
Japan
IN
India
mm
Diameter
Ring Sizer works entirely offline. Your measurements never leave your device. We don't collect, share, or sell any of your data. Ever.
"Used this app to measure ring size. It's accurate and it's really helpful."
Pradep12 · App Store Review
New sections on using Excel and Minitab for statistical process control. The “Operation Analytics” boxes show how data scientists use regression and simulation to solve OM problems.
: Predicting demand to optimize workforce and resource allocation. Summary of Contents
The 13th edition of Operations Management by William J. Stevenson
The builds on this legacy by addressing the most pressing challenges of the 2020s. While previous editions laid the groundwork in Six Sigma and Lean, this iteration introduces updated case studies on post-COVID supply chains, the integration of AI in forecasting, and sustainability as a core operational metric.
Modern operations are no longer just about efficiency; they are about responsibility. This edition places a heavy emphasis on "triple bottom line" thinking—balancing profit, people, and the planet. Readers explore how supply chains can be made more sustainable and the ethical implications of sourcing and production. 2. The Service Economy
The text is designed for ease of learning, featuring "Taking Stock" summaries, "Critical Thinking" exercises, and integrated Connect® digital resources.
Guides, tools, and charts to help you find the perfect fit.
Ring Size Chart
Complete conversion chart for US, UK, EU, Japan, and Australian ring sizes with diameter in mm.
How to Measure Ring Size at Home
5 free methods to find your ring size without visiting a jeweler — app, string, paper strip, and more.
Ring Size Calculator
Enter your ring diameter or circumference to instantly find your size in every international standard.
UK Ring Sizes (A–Z)
British letter-based sizing guide with full chart, Hatton Garden tips, and UK to US conversion.
Men's Ring Size Guide
Average men's ring sizes, measurement tips, and a complete chart for wedding bands and signet rings.
Secret Engagement Ring Sizing
How to find your partner's ring size without them knowing — clever tips for surprise proposals.