The Complete Beginner's Completely Incomplete Guide to Oxygen Not Included



New Hope.

1. Outhouses, wash basins and access to water

On the morning of the second day, your dupes will go to the bathroom. Even if there is no bathroom. The main goal for the first day (or "cycle" as days are called in ONI) is to take care of this impending yellow-water doom. To do that, you need to:


  • build an Outhouse.


The outhouse is found under Plumbing in the bottom left.



Wash Basin


After using an outhouse, dupes are covered in germs. They will spread these germs to anything they touch. So the secondary goal for the first day is to give your dupes a way to wash their hands after going to the bathroom. To do this:

  • build a Wash Basin


It is found under Medicine in the bottom left.

You aren't quite done yet - the outhouse and wash basin need resources to work.


Outhouses need dirt. This you will likely have dug up already. If not, mouseover brown tiles in the starting area until you find dirt and dig some up.

Wash basins need water. Dig your way to a nearby body of water and:


  • build a Pitcher Pump

It is found under Plumbing in the bottom left.


Note: for the pitcher pump to work, you also need to dig out some tiles underneath it so the hose thing becomes visible. (If you have set a dig command under your pitcher pump but dupes aren't digging it, they probably can't reach - build a ladder segment nearby.)

Pitcher Pump

Once dupes have filled the outhouse(s) and wash basin(s) with dirt and water you can give yourself a pat on the back - disaster averted.

If you didn't quite manage to avert disaster

  • You can have dupes mop up "accidents" with the Mop liquid spills command (bottom right, or press "M").

  • If any of the accident got into your clean water supply, germs will spread in your clean water. The easiest solution for now is to abandon that body of water and dig your way to a new, germ-free water source (*cough* or reload the game *cough*).

  • It is entirely possible to decontaminate germy water (in fact, we'll cover it later in this guide), but that is more of a mid-game thing.

  • For more on germs, see "Tip: germ basics"


The end of cycle 1. Water was nearby so I had time to get a lot done. Floors are 18 tiles wide in preparation for rooms (and room bonuses - which we'll cover later).

  • You can click & drag to measure out a distance. Then right-click to cancel.

  • An easy way to measure distances - like planning out a floor of a certain length - is with the dig command (bottom left or press "G").

Tip: measuring distances

  • To change it, click on the wash basin or sink and use the Set Direction command.

  • One use for this is to only have dupes wash their hands when leaving a bathroom. (They will get germs from using the bathroom, so washing their hands on their way to using it is pointless.)

  • You can specify that you only want dupes to wash their hands when passing in a particular direction.

  • On top of wash basins and sinks there is a green arrow that shows its use direction(s).

Tip: wash basin and sink "use direction"

You can set two types of priorities:

  1. Building Priorities

  2. Duplicant Priorities

​Building priorities affect what order dupes will do tasks like building, digging, supplying resources to outhouses or wash basins, etc.

Duplicant priorities make certain kinds of tasks - digging, building, etc. - more (or less) important for individual dupes. We'll look at duplicant priorities later in the guide.


To make sure your dupes get outhouses built during your first day, you can raise the priorities of the dig & build commands needed for that.


To change priorities, click on Priority in the bottom right (or press "P").

The default priority of tasks is 5. Choose 6 (or higher) for the necessary dig & build tasks to make sure they are taken care of first.

Priorities also affect the everyday maintenance of buildings. After 15 "visits" an outhouse will be out of order until emptied and restocked. To avoid future "accidents," you will want your outhouses to be emptied quickly. Also, to avoid the spread of germs you will want your wash basins to always have water.

It is highly recommended to raise the priority of your wash basins and outhouses. (I use 8 for outhouses and 6 for wash basins. But just make sure they are above your default values.)

The PANIC button. You can assign something "Top Priority." This will put the whole colony into alert until it is taken care of. (They will still sleep when tired, though.) This setting is marked "!!" in the priority selection screen (or press "P" and then "0" to select something to make top priority).

A note on priority creep. Speaking of default priority values, you might be tempted to keep raising more and more priorities to "get things done quicker." We've all tried this. It hasn't worked for any of us. Once everything is priority 9, nothing is priority 9.

Tip: getting the right things done first using Building Priorities

If a dupe is germy when they pass a wash basin or sink they will automatically wash their hands. But:

  • Only one dupe can wash their hands at a time at a wash basin or sink. If there are none free, dupes will not wait their turn. They happily run on and start spreading germs. To avoid this, build one wash basin for every outhouse.

  • Dupes will not intentionally look for a wash basin or sink after using an outhouse. You need to design your base so that they automatically pass one. A common way to do this is through door permissions.

​Controlling dupe movement using door permissions

When you have built a door (found under Base in the bottom left or by pressing "1") you can change its settings. One thing you can do is set a door so that it can only be passed in one direction.


If you build your outhouses on one side of the room and wash basins on the other, you can have the door on the side of the outhouses to only let dupes in, not out. That way dupes will pass a wash basin regardless of which direction they entered the room from.

Tip: making sure dupes wash their hands

  • A germy dupe spreads germs to things they touch - ladders, machines, beds etc.

  • To see germs in your base, click on the Germ Overlay in the top right. (Or press F9.)

  • If a dupe is germy, click on the dupe and then use the "Move to" command to make them run past a wash basin to wash their hands.

  • If germs manage to spread in your base you can have dupes disinfect things using the Disinfect Buildings button on the bottom right. (Or press "I".)

  • If germs are a constant problem, check to make sure: 1) you have a wash basin for every outhouse, and 2) dupes must pass a wash basin after using an outhouse. (It could also be a food related problem - we'll cover that later.)

Tip: germ basics


2. Beds (in temporary locations)



Dupes will get a debuff from sleeping on the ground.


(It isn't really a big deal and, to my shame, I often let them sleep on the ground for a cycle or two - or "a cycle or two" - before getting around to beds. I mainly included temporary beds this early in the guide to give the impression of being less heartless than I actually am.)

To avoid the debuff:


  • build each dupe a bed - called a Cot, found under Furniture in the bottom left.

You can build the beds in temporary locations, the goal is just just to avoid the debuff. However, there are a few things to keep in mind when deciding where to put beds, even temporarily.


Dupes will not sleep well if their sleep is interrupted. For standard dupes (certain traits affect this), their sleep is interrupted if:

  • It is too bright. For instance next to the printing pod, or if there is a shine bug nearby. (You can access the Light Overlay on the top right or by pressing F5.)

  • They are sleeping next to a snoring dupe

If you have a snorer (called a "loud sleeper"), leave two spaces - the width of a cot - between their bed and other beds.

You can assign beds to specific dupes, useful for instance to make sure a loud sleeper sleeps in the right bed.

3. Power, part 1: the hamster wheel and battery


Hamster wheel, Manual Generator

Your first source of power will be the Manual Generator, commonly known as the hamster wheel.

The hamster wheel generates power while a dupe pedals on it. As soon as the dupe stops pedaling, the hamster wheel stops generating power - and any machines hooked up to it stop working.

For machines to continue working after a dupe stops pedaling, you need to connect a battery to store power.

  • Build a Manual Generator (under Power, bottom left)

  • Build a Battery (also under Power in the bottom left)




The battery needs to be connected to the hamster wheel.

  • Use Wire (also found under Power) to connect the socket on the hamster wheel to the socket on the battery.

Laying wire will dig up earth tiles but will not destroy duplicant-built tiles. So if you want to keep your base tidy by hiding your wiring (and what kind of monster wouldn't want that?), build floor tiles for the wiring to go along.

On where to put things. You will develop a personal preference for where to put hamster wheels, batteries, etc. Until then, don't worry too much about placement. They are easy to move later if you want. (And we will be upgrading to coal power soonish anyway.)


4. Oxygen - the Oxygen Diffuser

The starting biome comes with some oxylite - tiles that emit oxygen as they slowly dissolve. They will keep you in oxygen for your first few cycles. With bathrooms and power sorted, it's time to sort out oxygen.

How to produce oxygen will depend on what asteroid you chose. There are several machines that can produce oxygen, and they each use different inputs to do so.


Since you are reading a beginner's guide, I will assume you started on the first asteroid in the asteroid selection screen. In both the base game and the DLC, the first asteroid has Algae - mouseover green tiles to find it.

  • Build an Oxygen Diffuser (under Oxygen, bottom left)

  • Using Wire (under Power), connect the oxygen diffuser to your power grid


Oxygen Diffuser


The oxygen diffuser turns algae into oxygen. Dupes will fill it up automatically, you don't need to do anything about it. (However, I usually change the oxygen diffuser's priority to 6 to make sure it gets done.)


The placement of the oxygen diffuser isn't hugely important, but putting it near a ladder system going through your base will make it easier for oxygen to flow.


You can save some dupe travel time by storing algae near the oxygen diffuser. To do this,


  • Build a Storage Bin (under Base, bottom left) near the oxygen diffuser

Storage Bin

By default, storage bins don't accept any materials. To change this, click on the storage bin. You can set it to accept all materials or any combination you want.

  • Change the storage bin to only accept Algae, found under Organic


The end of cycle 2. Hamster wheel, oxygen diffuser and algae storage sorted. The bathroom has doors and walls and qualifies for a (small) "Latrine" room bonus. Bedroom underway.

Research Station

  • There are a number of different gases in Oxygen Not Included.

  • The main ones you will come across in the early game are oxygen and carbon dioxide. And possibly some chlorine and hydrogen.

  • To see oxygen levels - and other gases - in your base, click on the Oxygen Overlay in the top right. (Or press F1.)

  • Over time, gases will settle in their own layers: hydrogen rises to the top, oxygen below it, then chlorine and at the bottom your carbon dioxide.

  • You can improve gas flow in various ways. An easy one is by having a somewhat spacious ladder shaft (or several). Instead of building a ladder with rooms immediately on both sides, leave an empty space on either side of the ladder. (Dupes can jump over one tile.) The extra space will improve airflow and also be useful for fire poles (Weeee!) and gas vents later in the game.

Tip: oxygen and gas flow

5. The Research Station

Lots of useful stuff needs to be researched before it unlocks. So now:

  • Build a Research Station (found under Stations, bottom left)

  • Connect it to your power grid (with Wire)


The research station requires dirt. So it isn't a bad idea to:

  • Build a Storage Bin (under Base) near the research station and set it to store Dirt (found under Cultivable Soil)


The end of cycle 3. Research station done. There was a fair bit of carbon dioxide in the starting area, so I spent some time digging out an area for air flow around the bedroom & bathroom. The dupes are eating dinner in the bathroom. Not ideal... but a problem for later.

Duplicant priorities versus Building Priorities

When dupes choose what to do, Duplicant Priorities come before Building Priorities.


By way of example, let's say we have a row of outhouses that need emptying. They are all set to priority 9 because things are about to go sideways. A dupe with a raised digging priority will keep digging - regardless of the Building Priority of the dig commands. A priority 1 dig command will win over a priority 9 command for anything else if the duplicant has a raised priority for digging.


Check "Enable Proximity"

There is a curiously well-hidden box that you will want to check fairly early on: Enable Proximity. Click on the cog in the upper right corner of the Manage Duplicant Priorities screen to find it. It makes dupes focus on closer tasks first.


Tip: Duplicant Priorities

Now that your basics are sorted this is a good time to set some priorities for your dupes. You can open the Duplicant Priorities menu by clicking on Priorities in the top right.

Here you can tinker with individual dupes' priorities for various tasks. You can raise priorities, lower priorities, or entirely forbid dupes from doing certain kinds of tasks. (Using the left & right mouse buttons.)

How to set your priorities will depend on what dupes you chose. Change priorities accordingly - research for researchers, building and digging for builders and diggers, etc.


Note: Later, you can grow your base to have enough dupes to have them focus on only one kind of task. But for now you will need to make sure one of your three starting dupes also takes care of the hamster wheel - so the base stays powered. And that someone empties and cleans the outhouses when they are full - so you don't have accidents.

  • The hamster wheel priority group is "Operating"

  • Wash basin and outhouse maintenance is "Tidying"

You can either raise those priority groups for some dupe or have a "general purpose" dupe without individual priorities, who will instead decide what to do based on Building Priorities.


Whatever you decide, it is a good idea to raise the Building Priorities for the hamster wheel (I usually have it on 6), the wash basin (I usually go with 6) and the outhouse (I have it on 8).


6. Food

Planter Box


The starting area has a decent amount of food. The red stuff growing around your base is Muckroot. Dig it up for easy calories.


To get your food production up and running, you'll need to do some research.


  • Research Basic Farming, found in the Food research branch

It won't take long. When done, you can build the Planter Box (under Food, bottom left).


  • Build (at least) 5 planter boxes for every dupe you have

  • Plant Mealwood Seeds in them


Mealwood Seed

​Note: After setting one Mealwood seed to be planted you can select the planter box and use the "Copy settings" command to issue plant commands for other planter boxes. (So you don't need to plant them all individually.)

You might not have enough Mealwood seeds to fill all planter boxes. Don't worry - harvesting can yield new seeds, and you will also unearth more seeds as you expand your base. You can also get more seeds by digging up Mealwood growing around your starter biome. (A benefit to this is that they will grow more quickly - click on a plant to compare "Wild Growth" and "Domestic Growth.")

  • There will be a decent amount of food growing in the starting biome

  • Dupes will not automatically harvest it

  • To enable (or disable) plant harvesting, click Harvest Plants in the bottom right (or press "Y")

  • Click & drag to enable (or disable) multiple plants

Tip: harvesting plants

  • Most foods have a "freshness" value

  • Freshness decreases over time


  • How quickly freshness decreases is determined by:

    • the temperature food is stored in

    • the atmosphere food is stored in

  • A Refrigerator slows freshness decline but does not stop it entirely

  • The Refrigerator is unlocked in Agriculture in the Food research branch

Tip: food freshness

7. Compost - dealing with polluted dirt

Your outhouses will produce polluted dirt. Researching Basic farming unlocks the Compost (found under Refinement in the bottom left). Dupes can use it to turn polluted dirt into dirt.

(I should perhaps mention that some players just ignore outhouse polluted dirt. I think it turns to dirt on its own over time. But I use composts.)



​​Note: polluted dirt can have germs. Transporting germy things gives dupes germs. So it is a good idea to have the compost behind a wash basin. (I usually put my compost with my outhouses.)

Another note: Updates to the game have made food spoil more quickly than before. Which means composts might be in frequent use. Composts get hot. So if you are new to the game and worried about dealing with heat and cooling, you can also just not put any composts in your base. (We'll cover heat and cooling later in the guide.)

To keep improving your colony you will need to do a lot of research. So let's cover some research basics.

  • There are three kinds of research in the base game. (The Spaced Out DLC adds a fourth kind.)

  • You don't need to remember what they are called, but it does seem like the kind of thing that should be included in a guide. So:

    • Novice Research

    • Advanced Research

    • Interstellar Research

  • Each kind of research requires its own research station.

    • Novice Research is conducted on the Research Station (available immediately)

    • Advanced Research is conducted on the Super Computer (unlocked under Advanced Research in the Colony Development research branch)

    • Interstellar Research is conducted in the Virtual Planetarium (unlocked under Computing in the Computers research branch)

  • Each research station requires a different material to conduct research.

    • Novice research: Dirt

    • Advanced research: Water

    • Interstallar research: Data Banks

Tip: research basics (base game)

  • Some research stations have skill requirements:

    • The Research Station has no requirements, anyone can use it
    • The Super Computer requires the Advanced Research skill (1 point in the research skill tree)

    • The Virtual Planetarium requires the Astronomy skill (3 points in the research skill tree)

  • All research stations, once unlocked, are found under Stations.

  • Data Banks, which are needed to conduct Interstellar Research, are gathered by sending rockets fitted with research modules into space, to uncover and explore planets.


  • Interstellar Research is only necessary for the more advanced rocketry-related unlocks. Meaning there is no rush (or need) to get into rocketry if you don't want to. (That said, there are some so-called "space materials" that aren't available on your starting asteroid. But they are only necessary for advanced builds.) (Basically, by the time you are ready to start building them, sending up a few rockets will be no big deal.


  • The first two kinds of research are the same. Just dirt and water.

Tip: research basics (Spaced Out DLC)


The end of cycle 4. Some more research done. Food, the Super Computer and the dining room are on their way. And ladder shafts for improved airflow.


8. Advanced Research - the Super Computer

The second kind of research (Advanced Research) requires two things: a Super Computer and a dupe with one skill point spent in Researching.


Super Computer

You unlock the Super Computer through researching Advanced Research in the Colony Development branch of the research tree. (You will need to research Employment first - you can't skip over research. But that's OK, we'll need that, too.)

When the research is finished,


  • build a Super Computer (under Stations)

  • connect it to your power grid

By now your dupes have probably started getting their first skill points. (If not yet, then soon.)


Whatever dupe you have chosen to be your researcher, spend their skill point in the Research branch of the skill tree to unlock the Advanced Research skill. Then they can use the Super Computer.

Something to consider: While you are still powering your base with a hamster wheel, power equals dupe time. For now, consider sticking to research you know you need either now or soon. Once you move on to coal power, feel free to go research-nuts.

(Disclaimer: I rarely follow this advice. I usually go research-nuts from the start. It leads to more frequent brownouts, particularly during the night. But I haven't found that to be a big deal.)


The end of cycle 5. Super Computer built. Mi-Ma got a skill point (put into research) and can now do advanced research. The research stations are built by the printing pod as it emits some light, so the stations get a "Lit workspace" 15% speed bonus.