Click the dish to harvest +1 biomass

Cell Strains

Hold Shift to buy 10

Cell Culture

How to Play

You run a petri dish. The cells divide on their own and steadily produce "biomass" (BM). The core loop is simple: cells generate biomass → spend biomass on more cells and upgrades → your rate rises → you generate even more biomass — a snowball that keeps growing.

Getting started: you begin with zero biomass, so click the dish to earn your first coins by hand. Once you have 15 BM, buy your first E. coli. From then on income accumulates automatically, and the share coming from clicks naturally shrinks as you scale — that is exactly the appeal of an idle game: it earns while you are away, and rewards you when you return.

Prestige: once your lifetime biomass this run reaches one billion (1e9), the "Prestige" option unlocks. Prestiging wipes your biomass, all cells, and all upgrades, but grants a permanent currency, "Medium" (ML). Each point of Medium adds +2% to your global output, kept forever and stacking across prestiges. Timing your prestige well lets you run faster and further next time.

Controls

· Click the dish: harvest biomass by hand — essential in the early game.

· Click a strain on the right: buy one cell of that strain; the cost rises with how many you own.

· Hold Shift and click a strain: buy up to 10 at once.

· Upgrades: buy milestone upgrades for a single strain (double its output), or global upgrades.

· Prestige / Stats / Settings: below the strain list; Settings lets you export, import, or clear your save.

Progress auto-saves locally (localStorage) every 10 seconds. Close the page and return, and offline income is settled (50% efficiency, capped at 12 hours).

Strain Field Guide

Every strain you unlock in the game is a real cell type. Here is what each one actually is in biology.

E. coliEscherichia coli

The classic model organism of molecular biology — it multiplies fast and is the workhorse host for genetic engineering and protein expression.

YeastS. cerevisiae

A single-celled fungus, one of the first microbes humans domesticated, and a key model for studying eukaryotic cells.

Fibroblastconnective tissue

The main cell of connective tissue; it secretes collagen and drives wound healing and structural support.

Stem Cellpluripotent

Capable of self-renewal and of becoming many cell types — the core of regenerative medicine and tissue engineering.

Neuronnerve cell

Transmits information through electrochemical signals; the basic functional unit of the nervous system.

Cardiomyocyteheart muscle

A muscle cell that contracts rhythmically on its own — it is what keeps the heart beating steadily.

Organoid3D culture

A miniature organ grown in 3D from stem cells, used for disease modeling, drug screening, and developmental research.

Synthetic Cellengineered

A life form built from an artificially designed genome — the leading edge of synthetic biology.

The Eight Strains at a Glance

Each strain costs more than the last and produces proportionally more. A new strain unlocks once you own five of the one before it, so the dish always grows in the same order.

#	Strain	Starting cost	Output each
1	E. coli	15 BM	0.1 BM/s
2	Yeast	100 BM	1 BM/s
3	Fibroblast	1,100 BM	8 BM/s
4	Stem Cell	12,000 BM	47 BM/s
5	Neuron	130,000 BM	260 BM/s
6	Cardiomyocyte	1.4 million BM	1,400 BM/s
7	Organoid	20 million BM	7,800 BM/s
8	Synthetic Cell	330 million BM	44,000 BM/s

Every purchase of a strain raises that strain's next price by a fixed percentage, so the tenth E. coli costs noticeably more than the first. This is what stops any single strain from carrying you forever.

Strategy: What to Buy and When

· Click only at the very start. Hand-harvesting scales with your total production rate, so it matters for the first minute and becomes irrelevant afterwards. Once cells are producing on their own, stop clicking and start planning.

· Always open the next strain. Each new strain produces far more per unit than the one before it. Buying five of the current strain to unlock the next is almost always better than buying a sixth of what you already have.

· But do not abandon the old ones. Because prices climb with every purchase, a wide dish is cheaper than a deep one. Topping up cheap early strains is often better value than one more expensive cell.

· Chase the milestone upgrades. Reaching 10, 25 and then 50 of a single strain unlocks upgrades that double that strain's output each time. Sitting just under a milestone is the most common way to leave production on the table.

· Global upgrades are the biggest jumps in the game. Three of them multiply everything you produce: a sterile bench, then an incubator, then CRISPR editing — worth ×1.5, ×2 and ×3 respectively. Each has a production requirement before it appears, so pushing your rate up unlocks the thing that pushes it up further.

Passaging: The Reset That Makes You Stronger

Once a run has produced enough biomass, you can passage the culture — wipe the dish and start over in exchange for culture medium, a permanent currency.

Every point of medium gives a permanent +2% to everything you produce, and it is never lost. Medium is awarded on a square-root curve, which has one important consequence: staying in a run long past the unlock point gives steeply diminishing returns. Doubling how long you grind does not double your reward.

The practical advice: passage as soon as the reward feels meaningful rather than waiting for a "perfect" run. Several quick passages compound faster than one very long one, because each restart runs on top of every bonus you have already banked.

Offline Growth

The dish keeps producing while the tab is closed. Offline production runs at half your normal rate and is capped at twelve hours, so there is nothing to gain from leaving it for days — checking in roughly twice a day collects essentially everything the game will give you.

Progress autosaves in your browser every few seconds, and the game also supports exporting and importing your save if you want to move it to another device.

Frequently Asked Questions

Is Cell Culture free, and do I need an account?: It is free and there is no account. The game runs in your browser and saves to your own device.
Do I have to keep clicking?: No. Clicking matters only in the opening minute. After that the cells produce on their own and the game is about what you buy, not how fast you click.
Does it keep earning when I close the tab?: Yes, at half rate, up to a twelve-hour cap.
Should I passage as soon as it unlocks?: Usually yes. The reward grows on a square-root curve, so waiting far longer than the unlock point yields much less than it feels like it should.
Where is my save, and can I lose it?: In your browser's local storage for this site. Clearing site data erases it, and it does not follow you to another browser or device — use the export option first if you plan to switch.
I unlocked a strain but cannot afford it. Is that normal?: Yes. Unlocking only reveals a strain; the first one is meant to be a goal you save toward for a while.

The Biology Behind Cell Culture

The game's vocabulary is borrowed almost intact from real laboratory practice.

· Passaging is a real and routine procedure. Cultured cells fill their vessel, growth slows, and researchers move a fraction of them into a fresh vessel with fresh medium so growth can continue. The game's version — clear the dish, keep the benefit — mirrors why it is done, if not the tedium of doing it.

· Culture medium is the nutrient liquid cells are grown in, and its composition genuinely decides how well they grow. Treating it as the game's permanent upgrade currency is a fair joke about how much of cell culture is really about the medium.

· The sterile bench and the incubator are the two pieces of equipment cell culture cannot happen without. The bench provides filtered airflow so nothing airborne lands in the dish; the incubator holds temperature, humidity and carbon dioxide steady. Contamination is the constant enemy in a real lab, which is why these are upgrades rather than decorations.

· CRISPR is a genuine gene-editing method, and its arrival changed what a lab can do to a cell line. Making it the largest multiplier in the game is not much of an exaggeration.

· The order of the strains is roughly the order of difficulty in real life. Bacteria and yeast grow fast and cheaply; primary human cells like fibroblasts are slower and fussier; neurons and heart muscle cells are harder still; organoids are three-dimensional cultures grown from stem cells and are genuinely at the research frontier. Synthetic cells — organisms running on artificially designed genomes — really do exist, and really are the far end of the scale.

Changelog

v1.0.0 · 2026-07-19 · Initial release: 8 cell strains, per-strain and global upgrades, prestige system, offline income, local save with import/export.