# Nic salt strength chart, the log to keep in your notebook > A nic salt strength chart to copy into your notebook, with the columns worth keeping, the formula to write down and two filled-in rows to check a mix. A shot poured, a bottle shaken, and three weeks later nobody remembers what strength it ended up at. Online calculators give you a number in the moment, almost never a record. A **nic salt strength chart** kept in your notebook fills that gap, provided the right columns are there from the very first row. Here is how to set one up, fill it in and read it back without redoing the sums in your head. ## Nic salt strength chart, what one row should hold A useful **nic salt strength chart** gives one row to every bottle you mix. That row records the date, the volume of base, the number and strength of the shots, the total volume, the amount of nicotine in milligrams and the strength obtained, followed by three follow-up boxes for flavour, steeping and impressions. The strength is always worked out the same way, by dividing the total nicotine by the total volume. A 50 ml shortfill topped up with one 10 ml shot at 20 mg/ml holds 200 mg of nicotine in 60 ml, which comes to 3.33 mg/ml. That figure, not the one printed on the shot, goes in the strength column. ## The columns to set up for every mix The columns fall into three blocks, in the order you fill the row in. The first identifies the bottle, the second carries the arithmetic, and the third keeps what the arithmetic cannot tell you. ### The identity block The mixing date opens the row, followed by the name of the shortfill or base you started from, its PG and VG ratio where the label gives it, and the batch number of the shot when the bottle shows one. That is enough to find a good mix again or explain a difference nothing else accounts for. ### The calculation block Five boxes, always in the same order. Volume of base, number and strength of shots, total volume, total nicotine in milligrams, and strength obtained in mg/ml. The milligram column looks redundant. It earns its place once a bottle is stretched or blended, with the same traceability logic as [the technical card for a CBD booster](/uk/cbd-booster/). ### The follow-up block Flavour takes two or three words, steeping goes down as the number of days before the first puff, and impressions get a score from 1 to 5 given after three sessions, once the novelty of the mix has worn off. ## The formula to copy at the top of the page Write the formula once and for all on the first page of the notebook. Strength obtained in mg/ml equals total nicotine in mg divided by total volume in ml. A 10 ml shot at 20 mg/ml brings 200 mg, two shots bring 400, and the total volume always includes the volume of the shots themselves. If your shot is marked 18 mg/ml, each one brings 180 mg. If the strength is printed as a percentage, 2% means 20 mg/ml, because 20 milligrams in every millilitre is 2 grams in every 100 millilitres. Stretching the 60 ml bottle at 3.33 mg/ml with 10 ml of zero nicotine base leaves its 200 mg untouched, but the strength drops to 2.86 mg/ml. The milligrams on record save you rebuilding the history of the bottle. The same logic applies when the last of an old bottle goes into a fresh mix. Twenty millilitres left at 5.71 mg/ml hold 114 mg, and added to 60 ml at 3.33 mg/ml, or 200 mg, they give 314 mg in 80 ml, so 3.93 mg/ml. Averaging the two strengths would give 4.52, a wrong figure. ## Two rows of a nic salt strength chart already filled in The standard case is a 50 ml shortfill with no nicotine, topped up with one or two 10 ml shots at 20 mg/ml. Here are the two rows, ready to use as a template. | Date | Base | Shots | Total volume | Nicotine | Strength obtained | Impressions | |---|---|---|---|---|---|---| | 06/10 | 50 ml shortfill, no nicotine | 1 × 10 ml at 20 mg/ml | 60 ml | 200 mg | 3.33 mg/ml | after 3 sessions | | 06/10 | 50 ml shortfill, no nicotine | 2 × 10 ml at 20 mg/ml | 70 ml | 400 mg | 5.71 mg/ml | after 3 sessions | The second shot does not double the strength. Nicotine goes from 200 to 400 mg, but the volume also rises from 60 to 70 ml, hence 5.71 mg/ml rather than 6.67. Check first that the bottle has room for the extra volume. On a nic salt strength chart, decimals are written down as they come. Rounding to 3 or 6 mg/ml is handy on a label, but it turns into an error as soon as that bottle goes into another mix. ## What throws a row out when you read it back Leaving the volume of the shots out of the total is the classic mistake. Dividing 200 mg by 50 ml gives 4 mg/ml instead of 3.33, a 20% overestimate that carries into later rows. The second trap is confusing strength with quantity. A shot at 20 mg/ml holds 200 mg in its 10 ml, not 20 mg, and that is the figure for the milligram column. Measuring by eye skews the series as well. A graduated cylinder or a measuring syringe puts a checked figure in the volume box instead of a guess. Then there is the row with no nicotine type. Two bottles at 3.33 mg/ml, one made with salts and one with freebase, cannot be compared on the impressions column, any more than fruit and coolness can share a single score in [a two column scoring method](/uk/strawberry-ice-method/). ## Nic salts and freebase in the same grid The calculation does not change from one form to the other. A nic salt shot at 20 mg/ml also brings 200 mg per 10 ml bottle, and the formula applies exactly as it stands. The difference shows up in the impressions column, not in the strength column. At the same strength, retailers describe nic salts as feeling smoother than freebase nicotine. Two rows at the same figure but with different nicotine types therefore cannot be compared, hence a dedicated column, ticked salt or freebase. A bottle that combines both types still takes a single row. The milligrams add up in the usual way, and the free note records how the shots were split. ## The safety notes that belong on the same page The page carrying the formula is also the place for handling notes. Wear gloves when pouring, work on a stable surface and rinse off any splash straight away, since nicotine must not be swallowed or left on the skin. Label every bottle you mix with the recipe, the strength and the date, which are the details of the matching row. Opened shots and finished mixes are stored closed and out of reach. ## Reading the chart back after a month After four weeks the chart can be read down the columns. A difference in strength you did not intend almost always points to a volume noted wrongly or a shot left out of the sum. Read the impressions column at equal strength. That is where steeping, the base or the type of nicotine shows its effect, since the strength itself no longer varies. A row that stands out deserves to be copied exactly next time you mix. A sum redone by hand on an old row works as a check. If it does not match, the milligram column shows where the error crept in. ## FAQ The questions that come up while filling in the first rows of the chart. ### How many nic shots go into a 100 ml shortfill? One 10 ml shot at 20 mg/ml gives 1.82 mg/ml in 110 ml, two shots give 3.33 mg/ml in 120 ml, and three give 4.62 mg/ml in 130 ml. The principle never changes, total nicotine divided by total volume. ### What is the legal maximum for a nic shot in the UK? Nicotine-containing liquid sold in the UK cannot exceed 20 mg/ml, and a refill container holding it cannot exceed 10 ml. Both limits are set by the Tobacco and Related Products Regulations 2016, which also cap the tank of a refillable device at 2 ml. ### Should the bottle be shaken after adding the shots? Yes, with the cap on, until the liquid looks even throughout. A poorly mixed bottle may not match the strength written on the chart for the first few puffs, which skews the impressions box from the start. ### Does steeping time belong on the chart? Yes, as the number of days between mixing and the first puff. The notebook does not decide for you, it lets you compare two identical rows with different steeping times and see whether the score moves. ### Can the chart live in a spreadsheet? Yes, and the formula only has to be typed once in the strength column. Keep the milligram column as a visible entry all the same, because it is the one you need when a bottle is stretched or blended with another. ## A nic salt strength chart you can still read in six months One row per bottle, nicotine in milligrams next to the strength, decimals kept and the nicotine type ticked are enough for the chart to answer the usual questions on its own. A calculator gives you a number, the notebook keeps the record. Start with the two template rows, then add the follow-up columns once the habit has formed. A well kept **nic salt strength chart** then sits alongside the other cards in the notebook, from hardware to flavours, under the same rule of traceability. ## Further reading - [CBD booster, the technical card for your notebook](/uk/cbd-booster/) - [Strawberry ice, separating fruit from coolness](/uk/strawberry-ice-method/) - [Jolie blonde, logging a classic tobacco liquid](/uk/jolie-blonde-log/) Editorial content for adult readers only. Nicotine is a highly addictive substance and vaping is not recommended for non-smokers. Vaping products are not for sale to anyone under 18 in the UK. This article is neither medical advice nor a buying recommendation.