How to Switch to and Use Fractional Dimensions in SOLIDWORKS

Fractional dimensions display inch values as fractions instead of decimals. They are useful on drawings for wood, sheet goods, construction-related parts, shop fixtures, and any workflow where the people reading the drawing expect fractions.

Change document units to fractions

1. Open the part, assembly, or drawing.
2. Go to Tools > Options.
3. Open the Document Properties tab.
4. Select Units.
5. Choose an inch-based unit system and set the length display to fractions.
6. Choose the denominator or precision that matches the drawing requirement.

This setting affects the active document. If you want new drawings to use fractional dimensions automatically, update the drawing template after confirming the settings.

Set the right denominator

The denominator controls how fine the fractional display becomes. Common drawing values include 1/8, 1/16, 1/32, and 1/64. Use the level of precision that is realistic for the process. A cabinet part may be fine at 1/16, while a machined part may still need decimal dimensions.

Do not use fractions just because they look cleaner. If the part requires tight tolerance control, decimal dimensions may communicate the requirement better.

Use fractions in drawings

After changing the document units, existing dimensions should update to the fractional format. Review the drawing carefully, especially dimensions with tolerances, dual units, hole callouts, or notes that were typed manually.

If only one dimension needs to show differently, select that dimension and check its dimension properties. Document-level settings are best for a consistent drawing, while individual dimension changes should be used sparingly.

Check rounding and tolerances

Fractional dimensions are rounded to the selected precision. Before releasing the drawing, compare critical values against the model and tolerance requirements. A dimension rounded to the nearest 1/16 may not be appropriate if the part actually needs a much tighter limit.

Use clear tolerance notes when fractional dimensions are acceptable. If the shop standard allows a general tolerance, make sure that note is present and easy to find on the drawing.

Save the setup for reuse

Once the drawing looks correct, save the document as a template if this format will be reused. That keeps future drawings consistent and avoids changing the same unit settings every time.