Ring-size labels are not universal. Select the exact source and target systems, anchor the conversion to measured inside circumference or diameter when possible, show the chart row and rounding, then confirm the seller's current label and fit method.

A transparent international ring-size converter specification that names both systems, preserves measured inside dimensions, versions the chart, shows nearest matches, and defers final fit to the seller and exact ring.

What this guide covers

Identify the source system, target system, chart version, and whether the starting value is a label or dimension.
Review the shared inside measurement, chart lookup, neighboring sizes, and nearest-match rule.
Confirm the current seller system and professionally size the exact finger for the intended ring.

Define both sides before converting

A converter should reject an ambiguous label instead of producing a confident but untraceable match.

Choose the named source system and target system; country names alone may not identify a seller's chart.
State the chart version and source because increments, half sizes, letter forms, and rounding can change.
Prefer measured inside circumference or diameter over a label copied without its system.
Preserve units and distinguish inside dimensions from outside diameter, mandrel markings, and approximate seller names.
Record the exact seller, ring width, geometry, and available size increments for final confirmation outside the conversion.

Convert through a visible physical anchor

The result is most understandable when every label remains tied to the inside dimension behind it.

Resolve — Find the source row
Match the entered label to the selected source chart and expose its listed inside circumference or diameter rather than skipping to another label.
Map — Look up the target system
Use that physical dimension against the versioned target chart and display the adjacent rows when no exact entry exists.
Disclose — Name the nearest-match rule
Show whether the result rounds up, down, or to the nearest available label and identify seller-specific gaps that still need confirmation.

A chart match is not universal equivalence

Conversion boundary
This preview converts nothing and stores no size. Regional and brand charts can overlap or differ, and a nearest match cannot guarantee joint passage, comfort, width response, resizing, stock, production, price, quote, or order acceptance. The current seller system and exact ring control.

International-conversion questions

Why do two charts give different converted sizes?

They may use different source dimensions, increments, rounding, half-size conventions, or revisions. Compare the measured inside dimension and identify each chart version.

Is the same number equal in every country?

No. Numeric and letter labels depend on the named system or seller. Never convert an isolated label without identifying its source.

Continue exploring

Review the conversion method
Read sizing help

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