Reading Shade Numbers and Oxidant Ratios in Salon

How a salon reads shade numbers and oxidant ratios, compares real colour costs with shipping, and keeps a purchasing file that holds up to review.

A salon reads a shade number by separating its parts: depth first, then primary and secondary tone, then any modifier the line adds. It reads an oxidant ratio by matching the developer volume to the target lift or deposit and to the grey coverage the service requires, not by habit. Both readings belong in writing, because a shade number and a ratio only mean something when the line, the developer and the timing are recorded together.

How does a salon read a shade number and an oxidant ratio?

A shade number is a code, not a name. Most professional lines build it from left to right. The first digit or pair of digits gives the depth, usually on a scale from 1 (black) to 10 or 12 (lightest blonde). The digits after it give the tone: a 0 is natural, a 1 is ash, a 2 is cool or iridescent, a 3 is gold, a 4 is copper, a 5 is mahogany, a 6 is red, and higher digits vary by manufacturer. A decimal or a letter after that is a modifier the brand defines in its own chart. The same number can mean different things in two lines, so the chart that ships with the tube is the only reliable key.

An oxidant ratio is the second half of the same reading. The developer volume sets how much lift or deposit the mixture can produce, and the mixing ratio sets how the pigment is diluted. A 1:1 ratio with a low volume deposits tone; a 1:2 ratio with a higher volume lifts and exposes warmth. The ratio is printed on the tube or in the technical sheet, and it changes with the line. Reading it means checking three things before mixing: the target depth, the starting depth, and the percentage of grey to cover. If any of the three is missing, the ratio is a guess.

A salon that wants to compare what it actually pays for those tubes, rather than what a list price suggests, can look at professional hair colour prices compiled with shipping included, which is the figure that lands in the purchasing file. The reading of the number and the reading of the invoice are the same exercise: both depend on the exact reference, not on the family name of the colour.

How does a salon compare the real cost of colour, shipping included?

List price is not cost. The cost of a tube is the price paid plus the shipping share plus any minimum order penalty, divided by the number of tubes that actually get used before the product expires. A salon that orders once a month and pays a flat shipping fee on a small order is paying more per tube than the invoice shows.

The practical method is to build a landed cost per reference. Take the invoice line, add the shipping and handling allocated across the order, subtract any volume discount that was actually applied, and divide by the units received. Do that for every reference the salon uses more than twice a month. The result is a single number per shade, and it can be compared across suppliers without arguing about list prices.

Three traps distort the comparison. The first is the promotional price on a line the salon does not use often, which looks cheap per tube but adds a shade that will expire. The second is the free shipping threshold, which pushes an order above what the salon needs and ties up cash in stock. The third is the difference between the price of a single tube and the price of a box, which is rarely the same per unit. A comparison that ignores shipping and thresholds is a comparison of catalogues, not of costs.

A salon can also compare its own landed cost against published comparisons for the French market, where references are grouped by brand and range with shipping included. That does not replace the salon's own invoice, but it shows whether a quoted price is in line with what other buyers report for the same reference.

What belongs in a salon purchasing file?

A purchasing file is the record that lets a salon answer a question six months later without guessing. It should hold, for each reference: the brand, the range, the exact shade number, the tube size, the mixing ratio, the developer volume used, the supplier, the invoice date, the unit price, the allocated shipping, and the landed cost per tube. It should also hold the technical sheet for the line, because the shade chart and the ratio change when a manufacturer reformulates.

The file should record what was used, not only what was bought. A column for services performed with each reference turns the file into a cost per service, which is the number that matters when a salon sets a price. A column for waste, meaning tubes opened and not finished, shows where the real cost sits.

A purchasing file also protects the salon in a dispute. If a supplier ships a different shade or a different volume, the file shows what was ordered and what was received. If a client reports an unexpected result, the file shows which batch and which ratio were used. Neither of those questions can be answered from memory.

Why does the shade chart change between brands?

Because each manufacturer defines its own tone digits and its own depth scale. A 7.3 in one line is not the same as a 7.3 in another, even when both call it gold. The depth scale itself can run to 10 in one line and 12 in another, and the neutral and ash families are placed differently. This is why a salon that switches suppliers cannot carry over a formula by number alone.

The safe practice is to keep a conversion note in the purchasing file for every reference the salon uses, listing the old number and the new number with the observed result. That note is built from the salon's own tests, not from a chart, because the chart describes the line and the note describes the client.

How can a salon verify a price before ordering?

Verification starts with the exact reference. A price is only comparable when the brand, the range, the shade number and the tube size match. A quote for a different size is a different product. Once the reference matches, the salon checks the shipping terms, the minimum order, the return policy and the delivery time, because those four conditions change the landed cost and the risk.

The second step is to compare more than one supplier for the same reference on the same day. Prices move, and a comparison made in one month does not hold in the next. The third step is to write the result into the purchasing file with the date, so the next order starts from a known figure instead of a fresh search.

A salon that follows this order, reference first, shipping second, date third, ends up with a cost per service it can defend. That is the point of the exercise: not to find the lowest number, but to know the number the salon is actually paying.

What to keep in mind

A shade number and an oxidant ratio are technical readings that belong in writing. A real cost is a landed cost, with shipping and thresholds included. A purchasing file is the record that turns both into a decision a salon can review. None of the three requires a ranking of suppliers or a judgement about which brand is better; each requires the exact reference, the date and the conditions of the order.

Colour work is a consumer purchase, and the same reading habits apply elsewhere: how a drug label is organised shows the official sections that matter, while electromagnetic exposure at home applies the same check to a device claim.

Change note: this page is part of the August 24, 2026 offline build. Source ownership and review dates are visible so future checks can be made without guessing.