Interactive tool unavailable without JavaScript. You can still read the measurement instructions, browse the guides, and record dimensions on paper. Do not treat sample outputs as calculated results.

MEASUREMENT REFERENCE / FREE CONVERTER

Tape Measure Fraction & Decimal Converter

Convert a tape reading such as 30 3/8 or 30⅜ inches to decimal inches and millimeters. Or enter millimeters and see the nearest 1/16 and 1/8 inch. No account, no tracking, and no guessed order size.

Interactive calculations require JavaScript. The displayed numbers are examples only; do not use them as calculated results. The accompanying educational instructions remain readable.

Worked examples

Tape reading	Decimal inches	Millimeters
3/16 in	0.1875	4.7625
30 3/8 in	30.375	771.525
36 1/2 in	36.5	927.1

Should I round before ordering?

Not automatically. Different blinds, shades and screen-frame products have different instructions for the measuring position, fractional precision, product deductions and even which height reading to submit. This tool only converts units. It does not select the measurement that belongs on an order form.

For example, Blinds.com's roller shade measuring guide describes product-specific measurement steps. Always consult the exact shade SKU and manufacturer manual before ordering; a displayed nearest 1/8 or 1/16 inch is a reading aid, not an instruction to round up or down.

Common mistakes to avoid

Mixing feet with inches: this tool accepts inches, not 2' 6 3/8. Convert feet to inches before entering.
Using a rounded estimate where a supplier requests an exact reading: record the original tape value first.
Using fractions with zero denominator or an improper numerator: recheck the tape before submitting.
Treating decimal and fractional results as measurements of the glass only; record what part of the frame or opening you actually measured.

Use the result in a specific project

For window screens, start with screen frame measurement. For window treatments, see inside-mount blinds. For uneven thresholds, use the door gap checker. The original readings and fit requirements matter more than the converted units.

Original diagram distinguishing a fractional tape reading, decimal inches and millimeters — **Reading reference:** Keep the same measured edge and original tape fraction. Unit conversion never changes a vendor's actual measurement or deduction rule. Instructional schematic, not to scale.