Length / Precision Converter
Enter any field to convert all units instantly. Reference: 1 mil = 25.4 µm = 0.0254 mm
🔬 Semiconductor：commonly µm / nm (e.g. 7nm process, lithography linewidth)
⚙️ Machining：commonly mm / inch (e.g. thread specs, tool dimensions)
📏 Precision Measurement：commonly µm / mil (e.g. roundness, flatness tolerance)
A PCB drawing specifies a hole diameter tolerance of ±0.5 mil (a unit common with US customers), but the CMM outputs measurements in µm. Engineers must verify the conversion to avoid rejecting good parts as defects. This tool provides instant conversion between mm, µm, nm, cm, m, inch, and mil — ideal for cross-unit drawing interpretation in electronics and precision machining.
Hole tolerance ±0.5 mil conversion: / ±0.5 mil = ±0.5 × 25.4 µm = ±12.7 µm / In mm: ±0.0127 mm / In nm: ±12,700 nm / Acceptance: CMM measured deviation ±10 µm < ±12.7 µm → Pass / Gauge selection: for a ±12.7 µm tolerance, use a gauge with resolution ≤ 1 µm (e.g. air gauge)
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