If you’ve spent any time hopping between No Man’s Sky’s billions of procedurally generated planets, you’ve almost certainly hit a point where you’re stuck waiting on a specific resource to progress. Maybe you need to upgrade your hazard protection to explore a radioactive wasteland, or you’re saving up for that fancy S-class freighter you spotted in a nearby system. If that resource is chlorine, you’re in the right place. Learning how to make chlorine in No Man’s Sky is one of the most useful early-game skills you can pick up, and it pays off all the way through endgame content too. I remember fumbling around for hours trekking across toxic planet surfaces looking for natural chlorine deposits when I first started, until a random player I met in a space station told me I could make it myself way faster, no toxic rain required.
What You Need Before You Start Making Chlorine
You don’t need any fancy endgame equipment to make chlorine, but there are a few basic prerequisites you’ll need to tick off first. The good news is most of these are unlocked within the first few hours of play, so even brand new players can start producing chlorine right away if they follow the main story path.
- At least a Tier 1 Personal Refiner (unlocked via the "Awakening" main story quest, roughly 1-2 hours into a new playthrough)
- A steady supply of salt, which you can gather from ocean planet shorelines, underwater mineral deposits, or occasional mineral outcrops on arid worlds
- 1 unit of carbon or condensed carbon to power the refiner for every 10 batches of chlorine you produce
- Empty inventory slots to store the finished product, especially if you’re making bulk chlorine for selling or large crafting projects
If you haven’t unlocked the personal refiner yet, you can use a portable refiner placed on any planet surface instead, you’ll just need to carry it with you if you want to make chlorine on the go. You don’t need a base to make chlorine, but having a permanent refining setup at your home base will make bulk production way easier down the line. Salt is the most efficient input for chlorine production by a long shot, so it’s worth taking 10 minutes to stock up whenever you fly past an ocean planet, even if you don’t need chlorine right away.
How to Make Chlorine in No Man’s Sky: Step-by-Step Process
Once you have all your supplies gathered, the actual refining process is super simple, even if you’ve never used a refiner before. There are two main recipes you can use, depending on how much extra oxygen you have access to. The basic recipe works for all players, while the advanced recipe gives you 50% more output for barely any extra work.
Start by opening your refiner interface, whether it’s your personal refiner, a portable unit, or a fixed refiner at your base. Add your carbon or condensed carbon to the power slot first, to make sure the refiner has enough fuel to run the full batch. Next, add your salt to the input slot. If you’re using the basic recipe, that’s all you need: 2 units of salt will refine into 1 unit of chlorine in roughly 10 seconds per batch with a personal refiner.
If you have extra oxygen to spare (you can get this from harvesting glowing flora on most planets, or from oxygen harvesters at your base), you can use the advanced recipe for far better results. Add 2 units of salt and 1 unit of oxygen to the input slots, and you’ll get 3 units of chlorine per batch instead of 1. That’s a huge jump in efficiency, especially if you’re making thousands of units of chlorine to sell. Using a large refiner cuts processing time by 40% compared to a personal or portable refiner, so if you’re planning to farm chlorine for units, it’s worth building one at your base as soon as you can afford the parts. I once tried to make 10,000 chlorine with a personal refiner on a long space flight, and it took me almost two hours of real time. When I switched to a large refiner at my base, the same batch took 45 minutes, and I got 50% more output from adding oxygen. Total game changer.
Creative Uses for Chlorine in Your No Man’s Sky Playthrough
A lot of new players assume chlorine is only good for selling for units, but it’s actually one of the most versatile resources in the game, useful for every playstyle from casual explorer to hardcore base builder. You’ll run into requirements for chlorine constantly as you progress, so having a stockpile on hand will save you a ton of time down the line.
First, chlorine is a core component for most hazard protection upgrades. Chlorine is a key component for crafting the Thermic Layer upgrade that lets you explore superheated planets without taking constant damage, which is necessary for finding some rare S-class upgrades and exotic resources. It’s also used for toxic protection upgrades, radiation filters, and even some hyperdrive upgrades that let you jump further between star systems.
For base builders, chlorine is used to make water filtration systems, advanced agricultural equipment, and even some decorative base parts that give your base a more high-tech look. If you’re into unit farming, chlorine is one of the most consistent low-effort ways to make millions of units fast. A fully automated salt farm on an ocean planet can produce enough salt to make 50,000 units of chlorine per hour, which sells for roughly 220 units each at most trade terminals. That’s over 10 million units per hour of passive income, for barely any work after you set the farm up. I used this exact method when I was saving up for my first S-class freighter, and I made enough units in three days to buy the freighter and outfit it with all the best storage and combat upgrades.
Common Mistakes to Avoid When Making Chlorine
Even though making chlorine is pretty straightforward, there are a few common mistakes new players make that waste a ton of time and resources. I’ve made almost all of these myself, so I can tell you first hand that avoiding them will make your chlorine production way smoother.
The first mistake is not stocking up on enough salt before you start refining. There’s nothing worse than getting halfway through a 10,000 unit chlorine batch, running out of salt, and having to drop everything to fly 20 light years back to the nearest ocean planet to restock. I always gather twice as much salt as I think I need, just to be safe. The second mistake is using the wrong refiner for the job. If you’re just making 50 units of chlorine for a single upgrade, a personal refiner is fine, but bulk production needs a large refiner to save time.
The third mistake is selling all your chlorine as soon as you make it. It’s tempting to cash out a huge stack of chlorine for millions of units, but nothing is more frustrating than realizing you need 200 units of chlorine for a hyperdrive upgrade 10 minutes later, and having to start all over. I always keep a stack of 500 chlorine in my inventory at all times, so I never get stuck when I need it for upgrades. Don't waste oxygen on chlorine production if you're running low on life support supplies - it’s not worth risking death just for extra output, especially if you’re exploring a harsh planet with no easy way to restock oxygen.
The last common mistake is only gathering salt from surface outcrops. If you take a submarine down to the floor of an ocean planet, you’ll find massive underground salt deposits that give you 10x more salt per minute than surface outcrops. You can even build a small underwater base next to a large deposit with automated miners, so you get a constant supply of salt without having to gather it manually.
At the end of the day, knowing how to make chlorine in No Man's Sky is a skill that will serve you no matter what playstyle you prefer, whether you're a casual explorer who just wants to see new planets, a base builder who wants to make the perfect home, or a hardcore player who wants to earn as many units as possible. It’s simple to learn, requires almost no rare resources, and the payoff is huge both for your progression and your in-game bank account. Next time you're flying past an ocean planet, take 10 minutes to stock up on salt, and you'll never find yourself stuck without chlorine when you need it most.
