Proof it at scale
Your boat's length sets the drawing. The number sits in the forward half with its real length marked, so you see at once whether 3 inches or 4 looks right and whether it fits the room you have.
Hull lettering, done to the rule
Letter the boat right the first time.
Type your registration number, boat name and hailing port. Bow and Transom checks the number's form, sets every letter at true size, draws a to-scale proof on a hull side, and prints full-size cut sheets you can tape to the boat or feed to a vinyl cutter.
Free to lay out and check. Lettering Pass $1.95/month or $19.50/year adds full-size sheets, the cut file and 25 saved layouts. Free during preview
ProofOH 1234 AB · Gull Wing · Cleveland, OH
What the federal rules ask
Six lines of regulation, checked for you.
| Rule | In plain words | Source |
|---|---|---|
| Form | Two state letters, then up to four numerals and up to two letters, or up to three numerals and up to three letters. No I, O or Q in the letters. | 33 CFR 174.23 |
| State letters | The federal list is not the postal list: California is CF, Michigan MC, Massachusetts MS, Washington WN. | 33 CFR 173 App. A |
| Size and style | Plain, upright block characters at least 3 inches tall, in a colour that contrasts with the hull. | 33 CFR 173.27(a)(2)-(3) |
| Spacing | A space or hyphen between groups as wide as a letter or numeral (not an I or a 1). | 33 CFR 173.27(a)(4) |
| Placement | Both sides of the forward half, reading left to right; no other number on the forward half. | 33 CFR 173.27(a)(1),(5); 173.19 |
| Documented recreational boats | Name and hailing port together on the hull, at least 4 inches tall; the port names its state. No state registration number under the federal rules. | 46 CFR 67.119, 67.123(c)-(d); 33 CFR 173.11(e) |
Your state issues the number and may add rules (sticker placement, for one). This site checks the federal frame and says so on every result.
Print it full size
The cut sheet splits each line across Letter pages at 100 percent, with a one-inch test square on page one. Butt the pages, tape them up, and judge it on the actual hull before anything sticks.
Cut it clean
The cut file is a true-size SVG made of letter outlines, not a font reference, so a vinyl cutter or sign shop gets exactly what you proofed. Five faces, all openly licensed.
Plans
Free to check. A coffee a month to cut.
Free
$0
- Number check with the state-letter table
- Lettering studio with live, to-scale proof
- All federal checks on every layout
- 1 saved layout in a Lettering File
- All five guides
Lettering Pass
$1.95 a month or $19.50 a year
- Everything in Free
- Full-size cut sheets, tiled on Letter pages
- Cut-ready SVG of letter outlines
- 25 saved layouts
Dealer Desk
$4.95 a month or $49.50 a year
- Everything in Lettering Pass
- Demo-boat number plates, full size (33 CFR 173.27(b))
- Batch number check, 100 at a time, with CSV
- 250 saved layouts
Free during preview. PayPal checkout is not switched on yet, so every paid feature is open to everyone and nothing is charged. When checkout opens, prices are exactly these; you can cancel any time in PayPal and keep the plan to the end of the period you paid for.
Guides
Read the rule before you peel the backing.
- The registration number, letter by letterForm, size, spacing and colour of the number on the bow.
- Documented boats: name, hailing port, official numberWhat a Coast Guard documented boat shows, and where.
- Validation stickersThe federal frame for the state sticker beside your number.
- Dealer and test boats: removable platesWhen a number may ride on a plate instead of the hull.
- Tenders and the suffix 1The dinghy that carries the mother boat's number.