Free LEGO Mosaic Designer — Design Brick Mosaics with Official LEGO Colors

LEGO studs sit exactly 8 mm apart, so every mosaic dimension is a multiple of 8 mm. A 16×16 tile is 12.8 cm square, one 32×32 baseplate is 25.6 cm, and the 48×48 plate used by the LEGO Art sets is 38.4 cm — which is why those sets fit standard 40 cm frames. Two 32×32 baseplates side by side make a 51.2 by 25.6 cm panel; four make a 51.2 cm square.

Multi-baseplate mosaics have a seam where the plates meet. The seam is invisible in the tile layer if the plates are butted tightly and mounted flat, but any gap shows as a hairline through the picture, so plan a mosaic that spans plates around a line of one colour where possible, or hide the seam inside a dark region. The designer shows dimensions in baseplate counts for exactly this reason.

The same grid can be built three ways, and they look different from arm's length. 1×1 tiles (part 3070b) are smooth and flat; the picture reads like a print, and the LEGO Art sets use them. 1×1 plates (3024) keep the stud, which adds a dot of shadow to every pixel and a texture that some builders prefer for portraits. 1×1 round tiles (98138) turn each pixel into a dot with baseplate showing between them — the halftone look — and are the cheapest of the three in most colours.

Mix them deliberately or not at all. Round tiles on a flat-tile background make a highlight glitter; a random mix looks like a parts shortage. The designer's stud preview shows the plate version; imagine the flat version as the same picture with the dots removed.

The palette lists official LEGO colours, but not every colour has been produced as a 1×1 tile, and of the ones that have, some exist in the thousands and some in the dozens. Black, white, the greys, red, blue, yellow and tan are plentiful and cheap. Dark Pink, Sand Green, Medium Azure or Bright Light Orange may be five to ten times the price per tile and available from a handful of sellers. Before committing a large region to a colour, search the tile on BrickLink and look at the number of lots and the price spread.

Substitution is normal. A portrait's skin tones can be built from Tan, Nougat and Reddish Brown, which are common, rather than the exact shade that costs more than the frame. The colour picker will tell you what a region is; the fill tool replaces it in one click, and the parts count updates so you can see what the substitution saves.

BrickLink sells by lot — one seller, one part, one colour — and charges shipping per seller, so an order with twelve colours from twelve stores costs twelve shipping fees. Sort the parts list by quantity, find sellers who stock your top three or four colours in bulk, and fill the small counts from the same stores where you can. LEGO's own Pick a Brick is simpler and often cheaper for common colours, slower for rare ones.

Add 3–5% to every quantity. Tiles get lost under the sofa, a few arrive scratched, and a colour that was one lot short means a second shipping fee for ten pieces. Tiles from different production years can differ slightly in shade — most visibly in white and in the greys — so order each colour from as few sellers as you can.

A finished baseplate is a rigid picture, and it hangs like one. Mount it on foam board or a plywood backer with double-sided tape, then frame it in a box frame deep enough to clear the tiles — 15 mm is plenty — or hang the backer directly with picture wire. Keep it out of direct sun: coloured ABS fades, and white yellows, over a few years on a bright wall. The PDF build guide, kept with the piece, is also the record you need if a tile ever pops off.