Enter your seed and this page builds your world and tells you where the Shimmer lake is: what your Compass and Depth Meter will read at it, with a map of the spot. It's always near the edge of the world on the jungle side, so the real question is how deep.
Find it in your world
Where it generates
The game's Shimmer pass picks a spot in the outer 11% of the world on the side away from the Dungeon, which is always the jungle side. The depth is anywhere from a little under the middle of the Underground layer down to about two thirds of the way through the Caverns, well above the Underworld. If 20,000 spots in that band fail, the band widens to the outer 20%.
We checked that against 3,500 generated worlds. In every one, the Shimmer was on the side away from the Dungeon, never more than 11% of the world's width in from the edge. Spawn sits in the middle, so the walk is always long. The map is for the depth, which changes a lot from seed to seed.
What it does to items once you find it is on the Shimmer transmutation list.
Walk from spawn
Tiles along the surface from spawn to the Shimmer's column.
Shortest walk on small worlds
Shortest walk on medium worlds
926986145Medium, corruption2,497 tiles east of spawnOpen map932237208Medium, corruption2,498 tiles west of spawnOpen map380052132Medium, corruption2,499 tiles east of spawnOpen map439677752Medium, corruption2,499 tiles west of spawnOpen map1344100427Medium, corruption2,499 tiles east of spawnOpen mapShortest walk on large worlds
Other finders
Item finderWhich chest holds Fledgling Wings, a Flying Carpet or any other generated loot.
Biome finderDungeon and jungle sides, the temple, mushroom biomes, hives and the desert.
Enchanted Sword finderSword shrines in your world, and seeds with one near spawn.
Pyramid finderPyramids, and where the Sandstorm in a Bottle and Flying Carpet are.
Sky island finderEvery floating island house and its Skyware chest loot.
Jungle Temple finderWhere the Lihzahrd temple is, and seeds with it close to spawn.
Dragon egg finderHuge Dragon Eggs, which the map draws the same grey as stone.
Life Crystal finderEvery Life Crystal in your world, nearest first.
Heart statue finderHeart, Star and Bomb Statues for your farms and traps.
Ore finderWhich ores your world rolled, and seeds with the set you want.