Maximise every mile of your plug-in hybrid

Plan smarter trips. Track real savings. Compare PHEVs before you buy. PHEVMax turns your plug-in hybrid's numbers into a strategy — tailored to your car, your tariff, and the trips you actually drive.

Try the free calculator

No sign-up needed to try · Works in any browser · Private by default

Free PHEV running-cost calculator

Pick any PHEV, enter your current car and a typical year's driving — see exactly what you'd save. Updates live. No sign-up needed.

The PHEV you're considering

Your current car

Fuel & electricity prices

Your typical driving

You would save / year
£—
— cheaper than your current car

Cost per mile

Current car
PHEV (blended)
PHEV on electric only
PHEV on petrol only

Annual spend

Current car
PHEV
Of which: electricity
Of which: petrol
Save your numbers — create a free account →
Log real trips, track real savings, auto-updating snapshots

A PHEV is only as cheap as its strategy

"How many miles on battery? When should I charge? Is it even worth plugging in for a short trip?"

Plug-in hybrids can be the cheapest cars on the road — or more expensive than an old diesel. It all depends on when you charge, how far you drive between charges, and whether you're burning petrol when the grid would be cheaper. Most PHEV drivers never find out because nobody hands them the numbers.

PHEVMax gives you the numbers — and the strategy. And if you're still deciding which PHEV to buy, use the calculator below to compare any two cars before you put down a deposit.

Everything a PHEV driver actually needs

Built by a PHEV driver who got tired of guessing.

Real cost vs your old car

See pounds saved — not a brochure number. Pick the car you used to drive and watch the gap grow with every trip.

Smart charging advice

Know when electric is cheaper than petrol. Know when a public charger costs more than a tank. Never plug in for no reason again.

Per-PHEV trip strategy

Every PHEV has different battery size, EV range, and real-world MPG. Type in your route and we tailor the advice to your exact car — how far on electric, how much petrol, whether to charge at the far end.

Break-even analysis

Above what petrol price does burning fuel become cheaper than the grid? We calculate it in real time based on your tariff.

Privacy-first

Your data lives in your own encrypted account, hosted in the EU. No ads, no trackers, no data sales. Cookie-free analytics.

Compare before you buy

Thinking about a PHEV but not sure it stacks up? Try the free calculator on this page — pick any PHEV, enter your current car, see the real running-cost gap. No account needed.

Three steps to start

You'll have your first real-cost number in under two minutes.

1

Sign up free

Email + password. 30 seconds. No card needed.

2

Pick your cars

Your PHEV from the catalog, plus the car you used to drive. We handle the maths from there.

3

Log trips, see savings

Enter odometer + battery % after each trip. Or use the postcode planner to estimate before you go.

Frequently asked

Is it really free?

Yes. Free forever for the core tracker. No ads, no data sales, no locked features. If it ever grows beyond what we can self-host, we'll be upfront about it.

Will it work with my PHEV?

We ship with 25 of the most popular UK PHEVs built in — Toyota Prius / RAV4, Volvo XC60/XC90, BMW 330e / X5 50e, Mercedes C300e / GLC 300e, Audi A3 / Q5 e, Range Rover Sport / P510e, VW Golf GTE / Tiguan eHybrid, Ford Kuga PHEV, Cupra Formentor, Lexus NX, Kia Niro / Sorento, Hyundai Tucson / Santa Fe, BYD Seal U, MG HS, Mitsubishi Outlander, and the Jaecoo 7 SHS. If yours isn't there, you can enter the specs manually in a couple of fields and everything still works.

I don't own a PHEV yet — can I still use this?

Yes — that's what the free calculator above is for. Pick the PHEV you're thinking about, pop in your current car's MPG, your tariff, and the kind of miles you drive, and you'll see whether the sums actually add up for you. No sign-up, no sales pitch. When you do take the plunge, the full app is waiting to track your real numbers from day one.

Do I need to install an app?

No. It runs in your browser — on iPhone, Android, Mac or Windows. On your phone you can tap "Add to Home Screen" in the browser menu and it'll open like a native app, offline included.

What do you do with my data?

Store it securely so you can access it. That's it. Data lives in an encrypted EU-hosted Supabase account, accessed only by you when you log in. We don't sell it, share it, or analyse it. We use GoatCounter for anonymous page-view counts (no cookies, no fingerprinting). You can export or delete your data at any time.

Who builds this?

A tiny indie team in the UK — PHEV drivers ourselves, fed up with the gap between brochure numbers and real-world running costs. Questions, bugs, feature requests: hello@phevmax.co.uk. We read every email.

Ready to see your real numbers?

Sign up in under a minute. Your first saving number appears after your first trip.

Get started — free