The Finance Ministry has a very slick and up to date website, Prix des carburants en France, that draws in prices from thousands of petrol stations across France.
You can start your search via département, commune or postcode, with the results displaying the name of petrol stations and supermarkets closest to your chosen location and the individual prices per litre.
It is possible to zoom in on individual towns and areas, and with a little bit of extra planning you could work out the best places to stop if you were travelling through France or around a region.
Best fuel prices in France
Often it is supermarkets that have the best price, even the supermarkets in smaller towns will be competitive, although many village pumps are extremely expensive.
These can often be more than 0.20 cents per litre extra than the supermarkets, if you really have to use one of these petrol stations it is almost worth just buying a minimum five litres and then driving to the nearest supermarket to top up.
Some stations will still have staff to take payment, but increasingly they are self service and open 24 hours a day.
Save fuel by driving sensibly
One of the advantages of driving in the French countryside is that the roads are usually quiet, with little traffic on them, so you can keep a steady pace and accelerate smoothly.
In towns and cities it is different, with much more stopping and starting you will be using more fuel, but again try to keep a light touch on the accelerator.
Car tyre pressures also play an important part in fuel economy, so I'd suggest keeping a small air compressor pump in the car as you can't always be sure pumps at petrol stations will be working and often you have to pay.
Also keep an eye on the condition of your tyres as many roads in the French countryside can be poorly surfaced, with sections sometimes damaged after heavy rainfall.
You may also be forced into driving in and out of soft verges when passing oncoming traffic, resulting in you banging into dips and bumps you were not expecting, so cast an eye over your tyres if you've had such an experience.
Air con can cost
Remember the air con uses fuel when running, and whilst it is a necessity when temperatures head towards 40C, try not to have it running when temperatures are more bearable.
Also don't drive around with your car boot full of heavy items and if you can, take roof bars and boxes off your car as these can cause drag and again see you use up more fuel than you need.
Anticipating what might happen on the road ahead is also a good skill to develop, plan to pass cyclists smoothly, be aware of when pedestrians might cross the road and keeping a sensible distance from the car in front will give you time to think.