Extracting oil from cannabis at home typically involves using heat and a carrier fat, a solvent like alcohol, or physical pressure to pull cannabinoids and terpenes out of the plant material. The method you choose depends on what equipment you have, what kind of oil you want to end up with, and how much effort you’re willing to put in. Most people start with a simple coconut oil infusion, which requires nothing more than a kitchen and a few hours.
Before any extraction, though, there’s one critical step that determines whether your oil actually works.
Decarboxylation: The Step You Can’t Skip
Raw cannabis doesn’t contain much active THC or CBD. Instead, it’s packed with their precursor forms (THCA and CBDA), which aren’t psychoactive and have limited effects until they’re heated. Smoking or vaping does this automatically, but when you’re making oil, you need to activate the cannabinoids yourself through a process called decarboxylation.
The simplest approach: spread your ground flower in a single layer on a parchment-lined baking sheet and bake it at 240°F for about 45 minutes. Some sources recommend 250°F for 20 minutes for a faster result. Either way, you’re aiming for the 200 to 290°F range. The flower should turn a light golden brown and smell toasty. Once it cools, it’s ready for extraction.
Temperature matters here for more than just activation. The aromatic compounds that give cannabis its flavor and scent, called terpenes, start evaporating at relatively low temperatures. Myrcene, one of the most common, boils off at around 168°C (334°F), and pinene even lower at 155°C (311°F). Keeping your decarb temperature at or below 250°F preserves more of these compounds. The heavier terpenes like caryophyllene and humulene can survive higher heat, but the lighter, more fragrant ones are the first to go.
Coconut Oil Infusion
This is the most popular home method because it’s forgiving, requires no special equipment, and produces a versatile oil you can cook with, put in capsules, or use topically. Coconut oil works especially well because its high saturated fat content binds efficiently to cannabinoids, which are fat-soluble.
The standard ratio is 7 to 14 grams of decarboxylated flower per cup of coconut oil. Using 7 grams gives you a milder oil, while 14 grams produces something considerably stronger. If you’re working with trim or shake instead of flower, you can increase the plant material since it’s less potent by weight. Some people use as much as an ounce of trim per half cup of oil.
Combine the decarbed cannabis and coconut oil in a slow cooker, double boiler, or saucepan on the lowest setting. The key is keeping the temperature between 160°F and 200°F for two to three hours. Going above 200°F risks degrading cannabinoids and burning off terpenes, while anything below 160°F won’t extract efficiently. A slow cooker set to “low” or “warm” usually lands in this range, but a kitchen thermometer takes the guesswork out.
After infusing, strain the mixture through cheesecloth into a glass jar, squeezing out as much oil as possible. Discard the plant material. The finished oil will solidify at room temperature if you used coconut oil, or stay liquid if you chose olive oil or another carrier. You can substitute almost any cooking fat, though coconut oil and butter (for cannabutter) remain the most common choices.
Alcohol Extraction
Solvent-based extraction using high-proof alcohol produces a more concentrated product than fat infusion. The result is typically a thick, dark oil or tincture, depending on how much solvent you evaporate off. This method pulls a broader spectrum of compounds from the plant, but it also requires more care.
Choosing Your Solvent
Use food-grade ethanol, ideally 190-proof or higher. Everclear is the most accessible option in many areas. Isopropyl alcohol is sometimes used, but it carries a higher risk of leaving behind residues that aren’t safe to consume. Hydrocarbon solvents like butane, methanol, and acetone are toxic for human consumption and pose serious fire and explosion hazards. Stick with food-grade ethanol for home extraction.
The Quick Wash Method
A “quick wash” with cold ethanol is the preferred technique for cleaner results. The idea is simple: cold alcohol extracts cannabinoids quickly while picking up far fewer unwanted compounds like chlorophyll, waxes, and plant fats that make the final product taste harsh and look dark green.
Start by placing both your decarboxylated cannabis and your ethanol in a freezer for at least 24 hours. The colder, the better. Then combine them in a mason jar, shake gently for 30 to 60 seconds (no longer), and immediately strain through a fine mesh filter or coffee filter. Speed is everything here. Longer contact time means more chlorophyll extraction and a worse-tasting product.
Once filtered, you need to evaporate the alcohol. The simplest approach is to pour the strained liquid into a wide, shallow dish and let it evaporate in a well-ventilated area away from any flames or sparks. Ethanol is highly flammable, so never use a gas stove or open flame to speed up evaporation. A small fan in a ventilated room works. What you’re left with is a sticky, concentrated oil.
Professional operations use vacuum ovens to remove residual solvents at lower temperatures, which preserves terpenes and ensures a cleaner product. Traditional heat purging destroys most of the volatile aromatic compounds. For home use, thorough air evaporation in a warm, ventilated space is the safest option, though some residual solvent will always be harder to remove without professional equipment.
Rosin Pressing: No Solvents Needed
Rosin is a solventless concentrate made by applying heat and pressure to squeeze resinous oil directly out of cannabis. The result is a translucent, sap-like substance that’s ready to use immediately with no purging or evaporation required.
At its simplest, you can press rosin with a hair straightener and parchment paper, though dedicated rosin presses give far more consistent results. The temperature and material you’re pressing determine the quality:
- Flower: Press at 180 to 220°F. Cold pressing (180 to 200°F) produces a lighter, more flavorful product with better terpene retention. Hot pressing (200 to 220°F) yields more oil but sacrifices some flavor. The sweet spot for most people is 200 to 210°F.
- Bubble hash or dry sift: Press at lower temperatures, 140 to 200°F. These starting materials are already concentrated, so they need less heat. Cold pressing at 140 to 170°F preserves the most flavor.
Yields from flower rosin are modest compared to solvent methods. You can expect roughly 15 to 25% return by weight from quality flower, meaning a gram of bud might produce 0.15 to 0.25 grams of rosin. Hash rosin yields are higher. The tradeoff is purity: since no solvents touch the material, there’s nothing to purge and no risk of residual contamination.
CO2 Extraction: The Professional Standard
Supercritical CO2 extraction is the method behind most commercial cannabis oils you’ll find in dispensaries. It works by pressurizing carbon dioxide past 1,071 psi at temperatures above 31°C, which puts it into a state where it behaves as both a liquid and a gas simultaneously. In this state, CO2 becomes a highly tunable solvent: adjusting the pressure, temperature, and flow rate lets operators target specific cannabinoids and terpenes with precision.
Professional CO2 systems have achieved extraction efficiencies as high as 92%, with typical yields ranging from 13 to 30% depending on the equipment scale and source material. This isn’t a home method. The equipment costs tens of thousands of dollars and requires specialized training. But it’s worth understanding because CO2-extracted oils are what you’re comparing your homemade product against.
How to Store Your Oil
Light, heat, and air are the three enemies of cannabis oil. Exposure to any of them causes cannabinoids to oxidize and degrade over time, weakening potency and flattening the terpene profile. Store your finished oil in an airtight glass container (amber or opaque is ideal) in a cool, dark place that stays below 70°F (21°C).
A tincture stored at room temperature will keep its potency for about a year. Refrigeration extends that to two or three years. If you’ve made a fat-based infusion like coconut oil, the fridge is a good default since it also prevents the carrier oil from going rancid. For truly long-term storage, freezing in a sealed container can push shelf life past three years, though you’ll want to let it come to room temperature before opening to avoid condensation getting into the oil.