SVG Blob Generator — make organic irregular shapes online (free)
An SVG blob generator makes those organic, irregular rounded shapes (blobs) you use as avatar backings, decorative splotches and image masks. Tune the number of points and the irregularity, swap the color, roll a new one, preview live, and copy the SVG or export a PNG. Design Cat is pure front-end, nothing uploaded — every blob is computed in your browser.
SVG Blob Generator is a free online tool from Design Cat that runs entirely in your browser — open it, do it, and download the result. Nothing is uploaded, there's no sign-up and no limits.
<svg viewBox="0 0 500 500" xmlns="http://www.w3.org/2000/svg" width="500" height="500"><path fill="#FB7185" d="M 444.6 250.0 C 443.6 301.4, 387.9 366.1, 336.3 399.4 C 284.6 432.7, 183.1 474.7, 134.6 449.8 C 86.2 424.9, 37.4 302.5, 45.6 250.0 C 53.7 197.5, 134.0 161.2, 183.4 134.7 C 232.8 108.1, 298.4 71.6, 341.9 90.8 C 385.4 110.0, 445.5 198.6, 444.6 250.0 Z"/></svg>
An organic shape generated live in your browser — export a single-path inline SVG (mask/recolor) or a transparent PNG.
How are blob shapes generated, and where do they fit?
A blob is that smooth, organic splotch with no sharp corners — hugely popular lately for avatar backings, hero decorations and image masks, because it feels softer and friendlier than a perfect circle or a rectangle. It's generated like this: take N evenly spaced points around a circle, nudge each point's radius by a little randomness (that's the 'irregularity'), then connect them with a smooth closed Bézier curve. More points and bigger nudges mean a more complex, more 'lopsided' shape. Design Cat runs this algorithm in your browser, so dragging the sliders reshapes the blob live.
Blobs have a few sweet spots. One is as an avatar or icon backing: drop a brand-color blob behind a user's avatar and it instantly reads livelier than a boxed photo. Another is hero decoration: place one or two large blobs in a low-saturation brand color with a bit of blur and the layout gains breathing room without feeling empty. A third is as an image mask: use the blob's path as an SVG clipPath or a CSS clip-path and a photo gets cropped into an organic shape — far more refined than a rounded rectangle. Just don't overdo it — one or two blobs is a tasteful accent; a screen full of them looks cheap.
Prefer SVG when you export: a blob is a single closed path — a few hundred bytes, lossless at any scale, recolorable via CSS fill and even morph-animatable. Copy the inline SVG directly; to use it as a mask, drop the path into a <clipPath> and reference it. If your target only takes bitmaps, use Download PNG for a transparent-background version. The whole generate-and-export flow runs locally in Design Cat — no upload, no account, unlimited.
How to use svg blob generator
- 1Use Points to set the blob's complexity (fewer = rounder, more = more ripples).
- 2Use Irregularity to set how 'lopsided' it is (0 = near-circle, high = very organic).
- 3Roll the Random dice for a brand-new shape until one feels right.
- 4Change the color, then Copy SVG or Download PNG to use it in your design.
Why use Design Cat's SVG Blob Generator?
- Local and private: pure in-browser smooth closed-curve math, instant.
- Clean single-path SVG: tiny, works as an avatar mask or decorative background, scales losslessly.
- Seeded randomness: every roll is a reproducible, complete shape — efficient to pick from.
Frequently asked questions
What do 'points' and 'irregularity' control?
Points is how many control nodes sit around the circle — more makes the shape more complex and finely rippled. Irregularity is how far each node's radius is randomly offset — 0 is near-circular, larger is more lopsided and organic. Together they define the blob.
Can I use it as an image mask to crop a photo?
Yes. Copy the blob's path, put it in an SVG <clipPath> and have your image reference it, or use it as a CSS clip-path — the photo gets cropped into that organic shape.
Can the exported SVG be recolored and animated?
Yes. It's a single path, so change the color with CSS fill; for a shape-shifting effect, morph between two blob paths (needs a library or SMIL).
Are random shapes reproducible?
Design Cat's randomness is driven by controllable parameters — the same points, irregularity and seed give the same shape. Roll Random to generate a new set, then copy when one looks right.
Updated · design cat team