Dilution Ratio Calculator
Enter a concentrate-to-diluent ratio from your own reference source, plus one known volume, to scale it to a full batch.
Mix
Scaling a ratio, not prescribing one
A dilution ratio splits a total volume proportionally between two parts. Given a ratio of a parts concentrate to b parts diluent, the concentrate share of any total volume is simply a / (a + b), and the diluent share is the remainder. This calculator applies exactly that arithmetic to whichever volume you already know.
It is deliberately generic: it works the same whether you're scaling a photographic solution, a cleaning solution, or any other liquid described by a documented ratio. It does not look up, suggest, or validate what the two parts should actually be.
Frequently Asked Questions
Where does the ratio come from?
From your own reference source — a manufacturer's label, a datasheet, or an archival reference. This calculator does not tell you what to dilute or in what proportion; it just does the proportional arithmetic once you already know the ratio, such as 1+4 or 1:9.
What does '1+4' or '1:9' actually mean?
Both describe a ratio of concentrate to diluent parts. "1+4" (five total parts) and "1:9" (ten total parts) are common shorthand across photographic and darkroom literature — this tool treats the two numbers you enter as the concentrate part and the diluent part respectively, regardless of which notation your source uses.
Can I work backward from how much concentrate I have?
Yes — switch "I know my…" to "Available concentrate volume" and the calculator scales the ratio up to tell you the maximum total batch (and matching diluent amount) that concentrate supports, which is useful when you're trying to use up a partial bottle without waste.
Is this safe to use for any chemical dilution?
This tool only performs ratio arithmetic — it has no information about what a given chemical is, how hazardous it may be, or how to handle it safely. Always follow the safety data sheet and handling instructions for whatever you're actually working with, and never treat this calculator as chemical-safety guidance.
Educational reference tool only — plain ratio arithmetic on a ratio you supply. Not chemical formulation or safety guidance; always follow the safety data sheet for any material you actually handle.