Paint on a stripe is an area, and width is half of it
This is the point of the page. A line is not a length, it is a rectangle, and the paint follows the rectangle. Take the defaults: a 330 by 195 foot field is 1,050 feet of perimeter, plus 380 feet of interior lines, so 1,430 feet of line. At 4 inches wide that is 476.67 square feet of paint per application. At 5 inches it is 595.83 — exactly a quarter more.
Now carry that through a season. At 300 square feet a gallon of mixed paint, one repaint at 4 inches is 1.59 gallons mixed. A first layout at 50 percent more is 2.38. Twenty repaints plus the layout is 34.16 gallons mixed, which at a 4 to 1 dilution is 6.83 gallons of concentrate. Widen the line by one inch and the season becomes 8.54 gallons of concentrate. That is 1.71 gallons more, or 25 percent, and nobody at the end of the season connects it back to the wheel setting on the striper in March.
| Line width | Sq ft an application | Season concentrate |
|---|---|---|
| 3 in | 357.50 | 5.12 gal |
| 4 in | 476.67 | 6.83 gal |
| 5 in | 595.83 | 8.54 gal |
| 6 in | 715.00 | 10.25 gal |
All four rows are the same field, the same coverage, the same twenty-one applications, the same dilution. Only the width changed.
Concentrate against mixed paint
Two different gallons get called the same thing. Mixed paint is what goes through the sprayer and what the coverage figure on the label refers to. Concentrate is what you buy and what sits in the shed. At a 4 to 1 dilution, one gallon of concentrate becomes five gallons of mixed paint, so the number you order is the mixed volume divided by five, not by four. Getting that off by one is the most common way a season order comes out 25 percent wrong.
The calculator reports both, and it derives the water as the remainder of the mixed volume rather than computing it separately, so the two halves always add back to the mixed total.
Coverage is not a property of the paint
It is a property of the paint, the sprayer, the operator and the grass. A stripe on dense, freshly mown, actively growing turf covers differently from the same stripe on thin dormant grass in November, and both differ from the number in the label test. The figure is a field here for that reason.
The reliable way to fix it is to measure your own. Fill the tank with a known volume, paint a known length at your working width, and see how far it got. Two fields into a season you will have a number that is right for your operation, and it will not be the label number.
What this page does not cover
Hard courts are a different job with different arithmetic — textured acrylic surfaces drink paint at rates that have nothing to do with grass, and the work involves masking rather than a wheeled striper. The court striping paint calculator handles that case.
What goes in the tank is also outside this page. Any product applied to turf beyond paint, and every question about what may be applied, at what rate and with what re-entry interval, is governed by the product label and by state and local rules. This page counts gallons of line paint and nothing else.
Line positions, permitted widths and which markings a field must carry come from the rule book your league plays under and from your facility standard, and they differ by sport, by level and by organisation.
Why no dimension on this page is a specification
Every distance here is something you type in. That is deliberate. Base paths, arc radii, goal sizes, line widths, run-off margins and safety zones are not universal numbers: they differ between youth, high school, college and adult play, between the organisations that sanction those games, and between one facility standard and the next. A page that hard-coded any of them would be wrong for most of the people reading it and would sound authoritative while being wrong.
So the rule book that governs your league is the authority on the dimension, and the facility standard your grounds department works to is the authority on how much room goes around it. Measure the field you actually have, take the target dimensions off the document that governs your play, and put those numbers in the form. What this calculator does is the arithmetic that follows.
Before anything goes into the ground
Irrigation mains, drainage, electrical runs to scoreboards and lighting, and old utility crossings all live under sports fields, frequently at shallow depths and frequently not where the as-built drawing says. Call 811 before you dig, trench, drive a stake, auger a post or set an anchor, and give the locate time to be marked. Private lines on the facility side of the meter are usually not covered by the public locate service, which is what catches out a crew that did everything else right.
Open fields are also the place people get hurt by heat and by machinery. A groundskeeper on a mower or an aerator in July is exposed on both counts at once, and neither risk announces itself.
Related pages: the court striping paint calculator for hard courts, the backyard court size calculator for laying out a playing area with its run-off, the field use hours calculator for how hard the field is being worked between repaints, and the general paint calculator for buildings.
Questions people ask
How much field paint does one field take?
Multiply the total line footage by the line width in feet to get painted square feet, then divide by the coverage of your mixed paint. A 330 by 195 foot field with 380 feet of interior lines is 1,430 feet of line; at 4 inches wide that is 476.67 square feet, and at 300 square feet a gallon that is 1.59 gallons of mixed paint per repaint. Divide by one plus the dilution ratio to get concentrate.
How do I convert a dilution ratio to gallons of concentrate?
Divide the mixed volume by one plus the ratio. At 4 parts water to 1 part concentrate, a gallon of concentrate makes five gallons of mixed paint, so 34.16 gallons of mixed paint over a season needs 6.83 gallons of concentrate. Dividing by four instead of five is the usual error and it overstates the order by 25 percent.
Does line width really matter that much?
Yes, and linearly. A stripe is length times width, so going from 4 inches to 5 is exactly 25 percent more paint on every application. Over a season of twenty-one applications on a single field, at the defaults here, that is 1.71 extra gallons of concentrate. Over several fields it multiplies again. The permitted width range comes from your governing body, but where you sit inside that range is a budget decision.
What coverage figure should I use?
Measure it rather than trusting a label. Fill the tank with a known volume, paint a known length at your working width, and divide. Grass coverage moves with mowing height, density, growth stage and how wet the surface is, and a figure from a smooth-surface test will always be optimistic. Once you have your own number, use it in the coverage field and the season figure becomes reliable.
Why does the first layout cost more than a repaint?
Because there is nothing underneath it. A repaint runs over an existing white line, which both guides the machine and gives the new paint a base to build on, so less of it is needed to read as opaque. A first layout on green turf has neither. Fifty percent extra is the default here, but it is a field, and on a field being laid out from scratch with string lines it can be more.