Water pH Guide: Understanding Acidity & Alkalinity

★ Water pH Guide · 2026

The pH of your drinking water, explained.

What pH actually measures, where common drinks sit on the scale, why most pH strips give bad readings, and what to look for on a bottled water label.

0–14 pH Scale 7 Neutral pH 10+ Designer Water
Independently Certified SANBWA ISO 22000 Kosher Halal GC Mark GFSI
★ The pH Scale

pH runs from 0 to 14, with 7 as neutral.

pH is short for "potential of hydrogen". It measures how acidic or alkaline (basic) a liquid is. The lower the number, the more acidic. The higher, the more alkaline. Each step on the scale is 10× the strength of the previous step.

024678101214
Acidic ←Neutral→ Alkaline
★ Common Drinks · By pH

Where your daily drinks actually sit.

Some drinks are surprisingly acidic. The pH of what you put in your mouth affects taste, mouthfeel, and over the long term, tooth enamel.

DrinkpH RangeCategory
Battery acid (reference)0.5 – 1.0Extreme
Lemon juice2.0 – 2.6Acidic
Cola / sparkling soft drinks2.4 – 3.0Acidic
Orange juice3.3 – 4.2Acidic
Coffee4.5 – 5.5Slightly acidic
Sparkling water (still pH; flavoured drops it)3.5 – 5.0Slightly acidic
Tap water (South Africa, typical)6.5 – 7.5Neutral
Purified bottled water6.5 – 7.0Neutral
Spring water6.5 – 8.0Near-neutral
Sea water7.5 – 8.4Slightly alkaline
Designer Water pH10®10+Alkaline
Baking soda solution8.0 – 9.0Alkaline
Household ammonia11 – 12Highly alkaline
★ Why pH Matters

Three reasons pH is worth knowing about.

The pH of your drinking water affects taste, the mineral profile, and over the long term may influence digestive comfort.

1

Taste

pH affects mouthfeel. Lower-pH water can taste "flat" or tinny. Higher-pH water, when paired with the right minerals, tastes smoother and fuller. The 96.9% taste-test result for Designer Water comes from this combination, not from pH alone.

2

Minerals

Alkaline water typically carries dissolved minerals (calcium, magnesium, potassium) that raise the pH. The WHO has noted drinking water can be a meaningful source of essential minerals — particularly in regions where dietary intake is variable.

3

Acid reflux research

Research published in JAMA Otolaryngology (Koufman & Johnston, 2012) examined alkaline water above pH 8.8 as part of a dietary protocol for laryngopharyngeal reflux. The study found the protocol matched or exceeded standard medication.

★ Three Ways To Test pH

How to actually measure the pH of water.

If you want to verify what's in your glass, here are the three common methods — ranked by reliability.

Method 1 · Best

Calibrated pH meter

Digital probe meters give accurate readings if calibrated regularly with buffer solutions. This is what we use in our quality lab.

✓ Reliable · Lab grade

Method 2 · OK

Lab test

SANBWA-accredited labs run titration tests for water producers. The most accurate option for batch verification, but not practical at home.

✓ Most accurate

Method 3 · Avoid

pH strips

Cheap strips are designed for liquids with Total Dissolved Solids above 150 ppm. Designer Water sits below 50 ppm — strips can't read it accurately.

✗ Unreliable on pure water

★ pH 10 · The Designer Water Range

If you want a verifiable high-pH water, here it is.

Designer Water reaches pH 10+ through a 14-stage filtration and remineralisation process. Verified per batch. Available in six sizes.

Frequently Asked

Questions about water pH.

What's the ideal pH for drinking water?

There is no single ideal pH. The South African National Standards for drinking water (SANS 241) specify a pH between 5 and 9.7 as acceptable. Most municipal tap water sits 6.5 – 7.5. If you want a higher mineral profile and smoother taste, alkaline water above pH 7.5 is the typical choice.

What is the pH of Designer Water?

Designer Water pH10® holds a verifiable pH of 10 or higher. Every batch is tested with a calibrated pH meter under our SANBWA and ISO 22000 protocols. The pH printed on the bottle is what's actually in the bottle.

Can I test pH at home with strips?

You can try, but for pure water you'll get unreliable results. pH strips are designed for liquids with Total Dissolved Solids above 150 ppm. Designer Water sits below 50 ppm — too clean for strips to read accurately. A calibrated digital pH meter is the only home-friendly accurate option.

Why does South African tap water pH vary by city?

Municipal water comes from different sources (rivers, dams, boreholes) and goes through different treatment processes in each metro. Johannesburg, Cape Town and Durban water all have slightly different mineral profiles and pH levels. SANS 241 keeps everything within 5 – 9.7, but the spread is real.

Does boiling water change its pH?

Slightly. Boiling drives off dissolved CO₂, which can raise the pH by 0.5 – 1.0 points temporarily. The water returns to baseline as it cools and re-absorbs CO₂ from the air. The effect is small and short-lived.

Is high-pH water safe to drink every day?

Yes. Designer Water pH10® is safe for daily consumption. SANS 241 explicitly allows pH up to 9.7 in drinking water, and the JAMA acid reflux study used water above pH 8.8 as a daily intervention without adverse effects. As with any water, the benefit comes from consistent adequate hydration throughout the day.

pH 10+ · Verified

The only bottled water in South Africa that prints its pH and proves it.

Designer Water tests pH on every batch. SANBWA + ISO 22000 audited. Six independent certifications. Order online or pick up from 5,500+ Waterpreneurs.

SANBWA ISO 22000 Kosher · Halal GC Mark · GFSI