Suminagashi Marbling Generator

Make a suminagashi-style marbled pattern: rings of floating ink dropped one inside another, then pulled into waves and hearts with tine strokes. The tool uses the maths of “Mathematical Marbling” (Lu, Jaffer, Jin, Zhao and Mao, IEEE Computer Graphics and Applications, November–December 2012). Each new drop of radius r at c pushes all the ink already there outwards, p → c + (p − c)√(1 + r²/|p − c|²), so ink keeps its area; each tine stroke slides the ink along a line, by z on the line and half as much every c mm away. Every ink is kept as an outline that is refined as it stretches. Choose rings from one centre, off centre, three or four centres or scattered drops, then no strokes, one stroke, a comb or a diagonal pull, and the colours. It prints at real size, filling the page or at the width and height you type. Download a PDF, a 300 DPI PNG or an SVG. Nothing is uploaded.

100% private — everything runs in your browser. Everything runs in your browser; nothing is uploaded.

How to make and print a suminagashi marbling pattern

1. Pick a preset, or choose where the drops go.
2. Set the number of drops, the drop radius and the number of inks.
3. Choose tine strokes: none, one, a comb, a comb both ways or diagonal.
4. Set the number of tine lines, the shift z and how fast it fades.
5. Choose the colours and fill the page or a width and height.
6. Download the PDF and print at 100% (Actual size), or the PNG or SVG.

What you can use it for

• Endpapers, wrapping paper and book covers
• Posters, cards and wall art
• Planning a real marbling session: ring spacing and comb strokes
• Backgrounds for packaging and labels
• Vinyl, screen-print and plotter layers from the SVG (one path per ink)
• Maths lessons on area-preserving maps

The 14 presets

Preset	Drops at	Drops	Radius	Inks	Tine strokes	Outline points	Colours
Concentric rings from one centre	one centre	20	14 mm	4	none	9,570	Indigo and cream
Black and white rings	one centre	24	12 mm	2	none	11,305	Black ink on white
Rings from an off-centre point	off centre	18	14 mm	4	none	7,810	Teal and sand
Rings from three centres	three centres	42	9 mm	4	none	11,205	Indigo and cream
Rings from four centres in a row	four in a row	48	7 mm	4	none	9,599	Plum and rose
Scattered drops (seed 4)	scattered	40	16 mm	4	none	10,235	Ochre, rust and cream
Rings pulled by one stroke	one centre	20	14 mm	4	one stroke (1, z 60 mm, halves every 15 mm)	13,738	Indigo and cream
Rings combed back and forth (6 strokes)	one centre	20	14 mm	4	comb (6, z 25 mm, halves every 8 mm)	13,228	Red, black and white
Rings combed both ways	three centres	36	9 mm	4	comb both ways (10, z 18 mm, halves every 8 mm)	12,819	Teal and sand
Rings pulled on the diagonal	one centre	18	14 mm	4	diagonal (4, z 30 mm, halves every 10 mm)	11,455	Plum and rose
Fine comb on scattered drops	scattered	40	18 mm	4	comb (10, z 12 mm, halves every 4 mm)	15,007	Ochre, rust and cream
Wide rings, one soft stroke	one centre	10	22 mm	2	one stroke (1, z 40 mm, halves every 30 mm)	5,935	Black ink on white
Real size 150 mm square, combed rings	one centre	14	9 mm	4	comb (4, z 20 mm, halves every 8 mm)	4,627	Indigo and cream
Real size 5 x 7 in, three centres	three centres	30	0.3 in	4	none	6,024	Red, black and white

Counts are worked out by the tool on US Letter.

Area, checked on the outlines

Step	Area before (mm²)	Area after (mm²)	Expected (mm²)	Result
Drop r = 12 mm at a point inside a 30 mm disc	2827.1	3279.5	3279.5	grows by πr² = 452.39
Drop r = 12 mm, 60 mm from a 10 mm disc	313.83	313.83	313.83	kept
Tine stroke z = 20 mm, halves every 8 mm, through a 30 mm disc	2827.1	2827.1	2827.1	kept (a shear)

Areas are of the tool’s own outlines (points at most 0.8 mm apart), and the expected value is the area before plus πr² for a drop that lands inside, or the area before otherwise.

Rings from one centre: outer edge r√k

Drops k (r = 10 mm)	Exact r√k	Outer ring drawn (from its area)
1	10.000 mm	9.995 mm
2	14.142 mm	14.137 mm
3	17.321 mm	17.316 mm
4	20.000 mm	19.995 mm
9	30.000 mm	29.996 mm
16	40.000 mm	39.997 mm

Tine shift: z × 2^(−d/c)

Distance d from the line	Exact (z = 20 mm, c = 8 mm)	Shift drawn
0 mm	20.0000 mm	20.0000 mm
4 mm	14.1421 mm	14.1421 mm
8 mm	10.0000 mm	10.0000 mm
16 mm	5.0000 mm	5.0000 mm
24 mm	2.5000 mm	2.5000 mm

Formulas: S. Lu, A. Jaffer, X. Jin, H. Zhao and X. Mao, “Mathematical Marbling”, IEEE Computer Graphics and Applications 32(6), November–December 2012, as set out on A. Jaffer’s “Mathematical Marbling” pages (read 13 November 2026). Here u = 2^(−1/c) exactly, so the shift halves every c mm.

What prints

Download	What is in it
PDF	The design at real size, one vector path per ink, with the drop and stroke counts and a check bar
PNG 300 DPI	The same sheet as a picture
SVG	One filled path per ink, oldest at the back, clipped to the frame

To edit an ink outline, use the SVG Path Editor; for a cutter that needs DXF, use SVG to DXF.

Which tool to use

You want	Use
Ink rings and combed marbled paper patterns	Suminagashi Marbling Generator (this page)
Stone veins like white marble	Marble Texture
Soft painted washes	Watercolor Texture
Smooth colour blends	Mesh Gradient Generator

Other tools: Marble Texture draws stone, Watercolor Texture soft washes, and the Mesh Gradient Generator colour blends.

Frequently asked questions

What is suminagashi?

Suminagashi is marbling with rings of floating ink: drops are touched to the surface one inside another, so each new drop pushes the earlier rings outwards, and the rings can then be blown or pulled into waves. This page draws that with exact maths; it does not simulate paint, water or paper texture.

How does a drop move the ink?

A drop of radius r at the point c moves every point p of the earlier ink to c + (p − c)√(1 + r²/|p − c|²). Every point moves straight away from c, and a disc of radius R about c becomes one of radius √(R² + r²): the ink keeps its area and the new drop fills exactly the hole of area πr². So k equal drops at one centre make rings whose outer edge is r√k (table below). This is the drop formula of Lu et al., 2012.

How does a tine stroke move the ink?

A tine stroke along a line moves each point along the line by z × u^d, where d is the point’s distance from the line and u = 2^(−1/c): the full shift z on the line, half of it c mm away, a quarter 2c mm away. It is a shear, so area is kept. A comb is several parallel strokes, back and forth.

How are the outlines kept smooth?

Each ink is a closed outline with points no more than 0.8 mm apart. After every drop or stroke, any edge stretched beyond 0.8 mm is split at the middle of where it came from, and that point is moved too, up to 8 times per edge, so the outline follows the true curve. The design is limited to 400,000 points.

What order are the inks drawn in?

Oldest first, newest on top. Each new drop sits in the hole the map opens for it, so the inks never overlap in the real pattern; the order only matters along shared edges.

Is the ink area really kept?

Yes, by the maths, and our tests check it on the outlines: the table below shows the area of a disc before and after a drop or a stroke.

Is it the same as the marble texture tool?

No. Marble texture draws veins of stone such as white marble. This page draws marbled paper patterns made by moving rings of ink.

Is it free?

Yes. There is no sign-up, no watermark and no limit.

Is anything uploaded?

No. Every outline is worked out by JavaScript in your browser. Nothing you type is sent anywhere or saved when you close the page.