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DPI & line interval calculator
Translate physical dimensions into rounded pixel dimensions, then move between DPI and millimeters per scan line. Nothing is uploaded and there is no sign-up.
Physical size to pixels
Enter the intended engraving size and image resolution.
Values must be finite and greater than zero, and the result must be at least one finite pixel in each dimension.
DPI ↔ line interval
Edit either field; the other updates automatically.
Common-looking values are not recommendations. Confirm spacing with an interval test on your machine and material.
What the math means
Two reciprocal views of spacing
Pixels = inches × DPI. Millimeter dimensions are divided by 25.4 before multiplying. Final pixel dimensions are rounded to whole pixels.
Line interval (mm) = 25.4 ÷ DPI. The reverse is DPI = 25.4 ÷ line interval in millimeters.
These conversions describe file size and nominal scan-line spacing. They do not determine whether your laser spot or material can resolve that spacing.
Quick conversion table
Common laser engraving DPI and line intervals
Use these reciprocal values to translate a laser software interval into lines per inch. Rounded labels do not replace an interval test on the actual machine and material.
| DPI / lines per inch | Line interval |
|---|---|
| 127 | 0.200 mm |
| 254 | 0.100 mm |
| 318 | 0.080 mm |
| 423 | 0.060 mm |
| 508 | 0.050 mm |
Official LightBurn references
- Interval Test — how to compare line spacing on the actual machine and material.
- 5 Steps to Perfect Image Engravings — LightBurn's image engraving workflow and test guidance.
For the image-preparation context, read the DPI and line interval guide or check the DPI glossary definition.