Cleaning Chemical Dilution Calculator
Turn any dilution ratio into the exact millilitres of concentrate for your bottle or bucket, plus what each filled bottle actually costs you.
Cleaning Chemical Dilution Calculator
Get the ratio right, and stop pouring money down the drain.
Plus 681.8 ml of water to fill 750.0 ml
- Concentrate
- 68.2 ml
- Water
- 681.8 ml
- Final concentration
- 9.09%
- Cost per filled container
- £0.25
- Fills per pack
- 73
- Solution per pack
- 55 L
- Cost per litre of solution
- £0.34
Add most of the water first, then the measured concentrate, then top up. Adding water to concentrate causes foaming and, with acids, splashing. Never mix products: bleach with an acidic descaler releases chlorine gas.
What dilution ratios actually mean
A ratio of 1:10 means one part concentrate to ten parts water: eleven parts total. In a 750ml spray bottle that is about 68ml of concentrate and 682ml of water.
Some manufacturers write ratios as one part in a total volume rather than one part to water. 1:10 read that way means 75ml concentrate in a 750ml bottle. The difference is around 10%, which matters for cost and for effectiveness on regulated products. Read the label carefully and, if in doubt, follow the manufacturer's stated millilitres rather than interpreting the ratio yourself.
| Ratio | Percentage | Per 750ml bottle | Per 5L bucket |
|---|---|---|---|
| 1:5 | 16.7% | 125 ml | 833 ml |
| 1:10 | 9.1% | 68 ml | 455 ml |
| 1:20 | 4.8% | 36 ml | 238 ml |
| 1:50 | 2.0% | 15 ml | 98 ml |
| 1:100 | 1.0% | 7.4 ml | 50 ml |
| 1:256 | 0.4% | 2.9 ml | 19 ml |
Over-dilution and under-dilution both cost you
Under-diluting: using too much concentrate: is the more common error and the more expensive one. It does not clean better. Excess surfactant leaves residue that attracts soil, so surfaces get dirty faster and floors go dull. On a busy round, habitual under-dilution can double your chemical spend.
Over-diluting is worse where it matters most. A disinfectant below its stated concentration may not achieve its claimed kill rate, which is a genuine problem in kitchens, washrooms, care settings and food premises. If a product has a validated contact time and dilution, that is the tested condition: anything weaker is unverified.
The practical fix is dosing equipment: wall-mounted dilution systems, dosing caps, or pre-measured sachets. They pay for themselves quickly on any team of more than two or three cleaners, purely on chemical savings.
COSHH: your legal obligations
Under the Control of Substances Hazardous to Health Regulations, UK employers must assess the risks of the cleaning chemicals their staff use and put controls in place. For a cleaning business this is not optional paperwork. It is one of the first things an HSE inspector or a commercial client's auditor will ask for.
- Hold a current safety data sheet for every chemical in use
- Complete a COSHH assessment for each hazardous product and each task
- Train staff on safe use, correct dilution and what to do if something goes wrong
- Provide and enforce the PPE the assessment requires: gloves, eye protection, ventilation
- Never decant into unlabelled bottles; every secondary container needs the product name and hazard information
- Never mix products: bleach with acidic descaler releases chlorine gas, and this injures cleaners in the UK every year