Advanced Chemistry

Lore & Background

In the cramped, oxygen-starved world of ONI's colony ship, chemistry is not an academic pursuit—it is the difference between a thriving settlement and a slow suffocation. The tech tree reflects this reality: early blueprints let a colonist boil water, strip oxygen from the atmosphere, and ferment basic nutrients. But as the colony expands, the simple reactions stop being enough. Crops need richer soil. The water loop demands purification beyond a single filter. Gases accumulate in ways that basic scrubbers cannot handle.

Advanced Chemistry is the moment the colony stops treating matter as a collection of separate elements and starts thinking in terms of molecular transformation. The equipment it unlocks lets colonists combine, break apart, and recombine substances in ways that were previously impossible, unlocking a tier of products that feed back into agriculture, atmosphere management, and even power generation. It is the blueprint that transforms a colony from 'surviving' to 'engineering its own ecosystem.'

Fans often describe unlocking Advanced Chemistry as the emotional turning point of a run—the point where the frantic early-game scramble gives way to the satisfying, almost medial loop of feeding inputs into a lab, watching the progress bar, and receiving exactly the compound you needed. It is Klei's way of rewarding long-term planning: you cannot shortcut your way here, and the colony that reaches it has already proven it can think in systems.

In Their Own Story

Mara pressed her thumb against the confirmation panel, and the haptic click was the only sound in the lab for a long moment. The Chemistry Lab hummed to life around her—its glass vessels filling with a pale amber reagent, the intake tray clicking as a conveyor dropped a slab of processed rock into the feed slot. She watched the progress indicator crawl. Outside the porthole, the colony's little grid of rooms glowed like a circuit board against the black. Three days she'd been balancing the water loop. Two days of crop failures. And now, finally, the compound that would let her triple the fertilizer output without dragging in another ton of raw ore. The lab chimed. She pulled the vial from the output slot, held it up to the dim panel light, and let herself exhale. The colony breathed with her.

Reader's Guide

Advanced Chemistry sits at the top of the Chemistry tech branch and is the final blueprint you research in that category. Below is a quick reference for what the Chemistry branch looks like as a whole and what the Advanced tier adds.

Tier 1 – Basic Chemistry: Unlocks the entry-level chemistry station. Allows simple reagent mixing and basic compound creation from raw materials like rock, water, and basic gases. This is where you first learn to produce foundational items for agriculture and atmosphere support.

Tier 2 – Intermediate Chemistry: Unlocks an upgraded processing station with additional reaction slots and the ability to handle more complex inputs. Expands the recipe pool to include mid-tier compounds useful for water purification, soil enrichment, and gas management.

Tier 3 – Advanced Chemistry: Unlocks the most capable chemistry lab in the game. This station handles the highest-value reactions, producing compounds that feed directly into advanced agriculture (premium fertilizers), long-term atmosphere cycling, and specialized utility items. It typically requires the most research investment in the branch and is the natural capstone for colonies that have stabilized their basic life-support loops.

Practical tip: Research Advanced Chemistry only after your water, oxygen, and power loops are stable. The lab consumes power and produces heat, so placing it in a well-ventilated, cooled area prevents it from becoming a thermal liability. Pair it with a conveyor-fed input system so a single colonist can keep it running continuously without micromanaging every drop.

Did You Know?

• In Oxygen Not Included, the Chemistry tech branch is one of several parallel research tracks, meaning a colony can choose to delay advanced chemistry and focus on power or agriculture first—there is no single 'correct' r
• The chemistry lab generates heat as a byproduct of its processing cycles, making thermal management a real design consideration even for a machine that is primarily about chemistry rather than power.
• Klei designed ONI's tech tree so that higher-tier blueprints do not replace lower-tier machines; instead, they add new capabilities, letting players run multiple chemistry stations in parallel for throughput.
• The game's closed-ecosystem design means that every compound produced in the chemistry lab ultimately feeds back into the colony's oxygen, water, or food loops—there is no 'waste' output, reinforcing the theme of total m