This free compost layer planner helps you stack a new pile layer by layer: browns, greens, water and cover, with thickness for each layer. Layering is the old, reliable way to build a pile that heats up, because every green layer sits next to dry browns that give it air and carbon. It runs fully in your browser, so nothing you type is sent to a server. You need no account and no sign-up to use it.
A pile built in layers composts more evenly than a pile tipped in all at once. Mixed-at-random piles form wet green clumps that go slimy, while layered piles keep air gaps open and let microbes reach every part of the waste.
To use the tool, fill in the boxes on screen and press the calculate button. You can change any number and calculate again as often as you like. The result updates at once, so you can test different plans side by side and see which one fits your garden best.
For example, take a 90 centimetre bin with 10 centimetre layers and 2 litres of water per layer. The tool shows 9 layers in total, 5 brown layers, 4 green layers, and 18 litres of water. Start and finish with a brown layer, so the pile holds moisture and smells stay inside.
In autumn, brown layers are easy, because fallen leaves are everywhere, so build the pile then if you can. In spring, greens dominate, so keep a stored sack of dry leaves beside the bin to keep every green layer paired with browns.
Tip: Water each layer as you build it. Watering only at the end leaves dry pockets deep inside that never break down.
Tip: Chop or shred thick stems before layering. Short pieces pack into even layers and rot far faster than long stalks.
Tip: Cover the top layer with straw or cardboard. A cover holds heat and moisture and stops the top drying into a crust.
The most common mistake is stacking thick green layers with no browns between them. A 30 centimetre slab of grass cuttings turns slimy and smelly within days, while the same grass split into thin layers with leaves between them heats up cleanly.
Common question: Do layers need to be exact? No. Roughly even layers work fine. The point is the alternation, not millimetre precision.
Common question: What counts as browns? Dry leaves, straw, shredded cardboard, and small twigs. They are dry, carbon-rich, and give the pile structure.
Common question: What counts as greens? Fresh grass, kitchen scraps, and soft plant trimmings. They are moist and nitrogen-rich, and they drive the heating.
First-time composters, school garden leaders, and allotment holders building a fresh pile each autumn use a layer plan. It also helps anyone whose last pile turned slimy and who wants a clear build order this time.
Keep a note of your pile dates and results through the season. After a few months you will see which mixes heated fastest and which plans finished on time. That record is worth more than any guess, because it comes from your own garden and your own waste.
Before you build the pile, read your plan once as if you were doing it tomorrow. Do you have the browns, the space, and the dates clear? If anything looks unclear, fix that line before you start. A plan that needs no guesswork works far better than a bigger plan that confuses you.
This tool is free to use as often as you like. Bookmark it and come back whenever you start a new pile or plan a harvest. A clear plan helps you compost with less smell, fewer flies, and more finished compost for your beds.
Remember that every result here is an estimate for home composting, not professional advice. Your local climate, your waste mix, and your bin type all shape the real result, so use the tool as a starting point and adjust it to your own garden.