Chemistry 20

Lore & Background

In the Factorio universe, the player's first encounter with chemistry is the moment a small chemical plant hums to life beside a line of water and oil extractors. Chemistry 1 grants the chemical plant, plastic bars, and sulfuric acid; Chemistry 2 adds the plastic pipe, letting fluids travel through compact routes instead of sprawling pipe networks. After those two entries, the research tree pivots toward plastics, advanced circuits, and the broader industrial web. There is no third, fourth, or twentieth chemistry node waiting in the background. The name 'Chemistry 20' occasionally surfaces in fan forums as a misremembered tier number, a joke about how many chemistry mods a player has stacked, or a shorthand for 'I've gone so deep into the chemical line that I've lost count.' None of these usages correspond to a real research entry. The game's data files contain no entry with that identifier, and no patch note, update log, or developer commentary references it. What the name does capture, in a purely figurative sense, is the player's feeling after hours of wiring up chemical plants, sulfuric acid loops, and plastic pipe spaghetti: the sense that the chemistry line has stretched far beyond the two official steps, as though an invisible 'Chemistry 20' is humming just past the edge of the research window.

In Their Own Story

The cursor hovers over the research screen, searching. Chemistry 1—done. Chemistry 2—done. The list scrolls, scrolling, past Advanced Circuits, past Robotics, past everything that has a name and a cost. No Chemistry 3. No Chemistry 10. No Chemistry 20. The player blinks, squints at the monitor, and mutters, 'I'm sure I saw it once.' They scroll back up. Two small icons, a chemical plant and a pipe, sit neatly in their little boxes, already greyed out with green checkmarks. Somewhere in the factory, a sulfuric acid pipe hisses softly, indifferent to the phantom tier that was never there. The player clicks away, queues up Plastic 1, and the factory keeps turning.

Reader's Guide

There is no 'Chemistry 20' to research, unlock, or slot into a prerequisite chain. The canon chemistry progression is straightforward: Chemistry 1 (unlocks the chemical plant, plastic bars, and sulfuric acid) requires the player to have previously researched Oil Refining and Plastic 1 prerequisites are not needed; Chemistry 2 (unlocks the plastic pipe) requires Chemistry 1. Both are low-to-mid-tier technologies, typically researched within the first several hours of a playthrough. After Chemistry 2, the tree branches into Plastic 1 and Plastic 2 (which add plastic plate and plastic pipe variants), and the fluid-transport line continues through Pipe, Pipe Robotic Arm, and Pipe To Ground. None of these are labelled 'Chemistry' beyond the initial two entries. For players building a save or sharing blueprints, the chemistry line's output—plastic bars, sulfuric acid, and plastic pipes—feeds into almost every later recipe: electronic circuits, processing units, and the long tail of advanced manufacturing. Blueprint sharing (Ctrl+B to copy, Ctrl+V to paste, or the in-game blueprint book) works identically regardless of which chemistry tier produced the components; the game does not gate blueprint use behind a technology tier. Community designs that lean heavily on chemical plants—such as compact plastic-bar farms or integrated sulfuric-acid loops—are shared freely on the Factorio wiki and community forums, but none reference a 'Chemistry 20' unlock. If you encounter the term in a mod pack or a fan-made tech tree, it is a custom addition with no bearing on vanilla progression.

Did You Know?

• Factorio's entire chemistry research line consists of exactly two technologies: Chemistry 1 and Chemistry 2. There is no Chemistry 3 or beyond in any published version.
• Chemistry 1 is one of the earliest 'quality-of-life' unlocks in the game, giving players the chemical plant that turns oil and water into plastic bars and sulfuric acid.
• The plastic pipe introduced by Chemistry 2 is often cited by veteran players as the single most important fluid-transport upgrade, because it replaces bulky pipe networks with a compact, stackable alternative.
• In the game's internal data files, technology entries are identified by short string keys; no key matching 'chemistry-20' or similar variants exists in any released version.