[theazureguy]

I got frustrated that every fuel price app just shows you what's cheap nearby. I wanted to know how stations actually behave: do prices go up faster than they come down, do supermarkets really save you much, how bad are motorway prices really?

So I built a scraper that hits the UK government's mandatory Fuel Finder API every 10 minutes and stores every price change. 90k records across 7,700 stations since January.

Some things I found that surprised me:

The rocket and feather effect is real and measurable. When stations raise prices the average move is 2.35p/litre. When they cut, it's 1.85p. There are also more up moves than down moves. I queried the raw history to check this rather than eyeballing a chart.

Motorway fuel is 28.4p/litre more expensive than everywhere else right now. That's about £14 extra on a 50L fill. Everyone knows motorways are expensive but I didn't expect the gap to be that wide.

The supermarket discount is only about 1.7p. I assumed it would be bigger.

Stack is Azure Functions, TimescaleDB, PostGIS, Next.js. The interesting thing about this project is the history. No public site shows how an individual station has priced over time or how a local cluster of stations react to each other. That's what I'm building towards.

Site: https://fuelinsight.co.uk

Happy to talk through the architecture or the data if anyone's interested.

[appreciatorBus]

Another insightful way to look at this is to include gasoline spot market data as a comparison.

I kept hearing about the vast profits of gas stations, so one day I started a spreadsheet of my gas purchases and kept it going over 10 years. When I tried lining up the graph of what I have actually paid per litre with a spot market graph, after converting for currency, units, taxes etc, they were almost identical, indicating extremely slim margins, if any. Yes there were differences, places in the graph where stations had likely made money on my purchase, but there were just as many where they likely lost money, unless I also stepped inside to but a snack.

[jacquesm]

You are correct. Non-chain gas stations often make only as little as one or two cents per liter, and that's before you look at pump maintenance, inspections, periodical tank replacements/upgrades/liners and other costs.

Manned stations really need that shop otherwise they'd go bankrupt.

Chains make a bit more money but mostly because they can play longer games with stock and options on much larger volume buys.

Source: former gas station owner.

[spockz]

And yet I see in earnings that companies like BP and Shell make record profits over increased gas prices. How come that they do profit but the station holders not? Are shell/bp increasing the margin harder and eating the station’s lunch?

[kitd]

The majors that do upstream (taking it out of the ground) as well as downstream (refining and selling it on the forecourt or wholesale) make their profits on the oil markets.

When crude is high, it's upstream that earns the income. When it's low, it's selling it to the customer.

Fun fact: when I worked at BP, the product with the highest margin on the forecourts was the Wild Bean coffee.

[qingcharles]

It's funny to think that BP is a coffee shop with a side-business in petrol.

McDonald's makes its largest margins from the soft drinks, according to an ex's brother who worked in their HQ. From a $1 drink, the cup, straw and lid is 5 cents, and the liquid is 3 cents.

[vkou]

Opening a gas station is a lot easier than acquiring mineral rights, drilling an oil well, refining that oil, and getting it to market. Oh, and your customers can't just drive across the street to your competitor because they are 1c/litre cheaper.

There's naturally going to be a lot more friction and a lot less pop-up competition and therefore a lot more margin on the supply side of things.

The station has no power to raise margin - they are in tight competition with every other low-margin station around them. The suppliers, on the other hand... If they invested into wells that aren't affected by the war 10 years ago, and their competitors haven't (or have, but can't supply all the world's oil needs), and there's a global supply shortage - they have lots of room to raise prices.

[badpun]

I think majority of the profits come from extracting the oil from the ground, much less from refining (more competetive - everyone can just build more refineries if margins become high enough), and the least from retail (gas stations).

[Ajedi32]

Yep. In short, this is an oil shortage, not a gas station shortage.

[semi-extrinsic]

The people who drill a hole in the ground and then a valuable product literally flows out of it, make more profits when prices of that product go up, compared to the refiners and resellers of the valuable product. I don't think this is mysterious?

Jokes aside, the upstream side has costs (both capex and opex) which are predominantly independent of the actual oil price, but income which is tied to it.

It's like with NVIDIA: their cost of producing a B200 is not directly related to the cost of (and demand for) Claude Code, but what they can charge for a B200 is.

[gostsamo]

Reuters had a material on the topic. The big producers have trading desks that can optimise based on spot prices and redirect tankers as needed.

[zipy124]

A lot of their record earnings come from trading revenues as well, as they all effectively have in-house trading desks to hedge risk.

Not nearly as much profit as Vitol made but they make large sums too.

[mschuster91]

> How come that they do profit but the station holders not? Are shell/bp increasing the margin harder and eating the station’s lunch?

Here in Germany, many stations aren't even involved in selling the gas. That's what that magical line "Verkauf von Kraft- und Schmierstoffen im Namen der <Firma>" on the receipt says - the fuel and oil are on paper/for accounting purposes sold by the oil company whose brand is on the flag.

Independent gas stations (e.g. in Bavaria, the Allguth chain) exist, and they buy, store, distribute and sell their fuel on their own, but in the end everyone is bound to the same few refineries - virtually all (!) of Eastern Germany, Berlin, the Berlin airport and Western Poland for example depend on the PCK refinery complex in Schwedt [1], in Bavaria 2/3rd of the market is supplied by the two Bayernoil refineries in Vohburg and Neustadt [2], the rest by Gunvor (ex-Esso/Exxonmobil) [3].

No matter if you are an independent or brand-owned gas station... there is about zero competition on the supply side. It's all the same gas and diesel, the only practical difference is the additives for the ultra-high-octane fuel. And that in turn means very little competition at the pump, and owners of independent gas stations being hit the hardest.

There's a reason why Allguth stations more resemble a 24/7 supermarket, restaurant and beer hall than a gas station.

Oh and the supply side competition is pretty bad even for refineries. Refineries are fitted to refine only a specific composition of oil - that's the distinctions sweet/sour and light/heavy. For that reason, the US can't process a bunch of its own oil [4], which means the US is actually dependent on Canada and Mexico [5] to meet its oil product demand. A refinery which, like almost all are, is tuned to a specific country's (or, worse, a specific oil field in a specific country) composition is in a real bind, should the supply chain ever get screwed up. The Russian invasion of Ukraine was bad enough, the Iran war was what could very well be the final, fatal blow to many a refinery, especially in Asia.

Retrofits are possible to allow a refinery for light sweet oil to process heavy sour oil (i.e. add a sulphur removal stage to deal with that, and a cracking stage to deal with heavier molecules), and it is possible for a refinery that is tooled for heavy sour oil to run on light sweet oil without modification - but it is seriously throwing wrenches into the financials, and that's a blocking issue in our money driven world [6].

[1] https://www.faz.net/aktuell/wirtschaft/unternehmen/pck-raffi... / https://archive.ph/qtvd8

[2] https://de.wikipedia.org/wiki/Bayernoil

[3] https://de.wikipedia.org/wiki/Gunvor_Raffinerie_Ingolstadt

[4] https://www.afpm.org/newsroom/blog/how-much-oil-does-united-...

[5] https://atlasinstitute.org/heavy-oil-heavy-dependence-how-us...

[6] https://www.forbes.com/sites/rrapier/2026/04/05/debunking-a-...

[theazureguy]

Good shout. DESNZ publishes weekly wholesale rack prices and they are OGL, so there is no barrier there. The interesting bit isn't just showing the gap; it's the propagation lag. Wholesale spikes and pump prices follow within days. Wholesale drops and pump prices take their time. That asymmetry is basically what I built this dataset to measure. Adding the wholesale series as a reference line is on the list.

[christina97]

You’re absolutely right!

[gruez]

>The rocket and feather effect is real and measurable. When stations raise prices the average move is 2.35p/litre. When they cut, it's 1.85p. There are also more up moves than down moves. I queried the raw history to check this rather than eyeballing a chart.

Comparing the absolute size of price rises vs drops doesn't make sense, because it could very well be an issue with the underlying price (eg. crude oil or whatever). It seems hardly fair to blame gas stations for being slow to lower prices, when refineries are still also slow to lower prices. Same for blaming refineries when the global market is slow to lower prices.

[theazureguy]

yeah that's fair, without wholesale rack prices as a baseline you can't really isolate station behaviour from what's happening upstream.

[gruez]

>without wholesale rack prices as a baseline

The US government publishes data on this (eg. https://www.eia.gov/petroleum/gasdiesel/). The UK government might have something similar. Barring that, you can use Brent crude as a proxy.

[fredoralive]

For the "supermarket saving", did you include Asda in the supermarket pool, or as a general pool? They seem to be rather less price competitive than other supermarkets, I'd presumably because of the recentish private equity takeover involving petrol station operator Euro Garages meaning they've kinda opted out of the petrol price war (they're hardly likely to want to undercut their existing forecourts).

Although the other recent private equity takeover of Morrisons led to some sort of deal with Motor Fuels Group to operate their petrol stations (but no ownership stuff in this case?), but they're seemingly still being competitive with Sainsbury's and Tesco's.

[theazureguy]

Yeah Asda is in there. I match on brand name directly rather than the API's is_supermarket flag because that flag is all over the place (loads of Asda stations don't have it set). So it explicitly checks for Asda, Tesco, Morrisons, Sainsbury's, Co-op, Costco.

Your point about post-PE Asda is interesting, I've noticed it too. If you want to see how they compare individually you can check the brands page on the site, shows each supermarket chain as its own line. Pretty easy to split the supermarket aggregate out per brand too, would probably show Asda creeping back towards the independents since the takeover. Might add that.

[lotsofpulp]

It is well established that Costco sells Top Tier brand fuel at zero margins, so you could have just tracked Costco prices. In the US, Walmart, Kroger, and Albertsons also sell fuel at near zero margins, but it’s not Top Tier branded.

[prennert]

Quite interesting that some service stations did not report a change for weeks.

Like this one: https://www.fuelinsight.co.uk/stations/7fd603ba12430695595b2...

I wonder if your API queries get capped / paginated or if those stations really do not report any changes for so long. It would be interesting to know if there is a pattern with those low frequency updates.

[shantnutiwari]

> I got frustrated that every fuel price app just shows you what's cheap nearby.

Yes it gets a bit tiring. Considering the difference is usually 0.01 penny per litre, so it doesnt make a big difference. But it does mean in a panic everyone runs to that one station and it runs out

I never understood the logic of driving 20 miles to save 0.01p/litre (but then I live in the countryside, maybe its different in cities-- though cities also have huge traffic so you are wasting the same amount of fuel)

[King-Aaron]

My company network wont let me see newly registered domains, so I couldn't check out your build (I'll wait until I get home!), but our local state government set up a tool called Fuel Watch that does a pretty good job of showing the today/tomorrow pricing based on post code.

Probably not doing exactly what your tool does, but you might be interested: https://www.fuelwatch.wa.gov.au/

[hermitcrab]

Are you aware the some of the Fuel Finder data is total garbage?

https://successfulsoftware.net/2026/03/29/stop-publishing-ga...

Why did you make 'Esso' and 'Shell' the same colour in your brand chart?

[theazureguy]

Yeah aware of some data quality issues in the feed, bad coordinates, missing brands, occasional obviously wrong prices. I filter out anything outside 100-300p and exclude stations flagged as closed but there's definitely still noise in there. check the methodology page for the full detail on how i clean it.

On the colours, esso and shell are both red brands so they ended up close on the chart. will fix that.

[hermitcrab]

The Shell logo is mostly yellow, isn't it?

[theazureguy]

shell's logo does have a lot of yellow but morrisons has already claimed yellow on the chart.

[zpeti]

I built the very first prototype of petrolprices.com almost exactly 20 years ago I think.

One man job, 2 weeks I think and we launched.

Nice project :)

[theazureguy]

petrolprices.com is still going strong. nice to meet one of the OGs.

[yzydserd]

> So I built a scraper that hits the UK government's mandatory Fuel Finder API every 10 minutes and stores every price change. 90k records across 7,700 stations since January.

Only 1 change per station per week on average? Fewer than I expected. Not sure I'd call it a scraper, myself.

157p/L national average is about 8 USD/G.

[traceroute66]

> Only 1 change per station per week on average? Fewer than I expected.

My uneducated guess is it correlates to the weekly delivery of fuel. ;-)

[rootusrootus]

> 157p/L national average is about 8 USD/G.

Europeans seem to be far more comfortable with Pigovian taxes than Americans. Or does it even come up for discussion when people are referencing the retail price at the pump?

[pacificpendant]

It definitely does come up. A common complaint in the UK is that there are two types of tax added to fuel prices; fuel duty and VAT. So you end up paying VAT on the fuel duty you’re paying.

We have had fuel price protests too, sometimes involving blockades by hauliers. https://en.wikipedia.org/wiki/Fuel_protests_in_the_United_Ki...

[theazureguy]

fair point on scraper, it's more of an ingest pipeline really. the 90k is total price records across 7,700 stations since january, stations update a few times a week on average. the 10 min polling catches every move when it happens. the value is in the per-station, history over time, not the raw volume.

[dkga]

Hi, economist focused on monetary policy/inflation here! That data would make for a cool empirical paper that could help central banks and other economists better understand price dynamics around a significant shock. Are you interested in discussing it?

[theazureguy]

Absolutely, feel free to reach out. contact details are on the site. would love to see how I can help!

[icanhasjonas]

I made something similar for Thailand in the peak of the crisis .. all on GitHub, regional concerns and such..

https://www.fuelthai.com/

[bossyTeacher]

Since you are happy to talk on this topic, can I mention your privacy policy page?

If a new user clicks on Accept, he has no (normie) mechanism to revoke that as the choice is stored in local storage and it doesn't expire.

[theazureguy]

Ahhh thanks for that. I have deployed a change to fix this ASAP.

[jonahx]

What did you use for the UI widgets, graphs, etc? Looks like tailwind is being used but is the design bespoke or a CSS/dashboard lib?

[theazureguy]

bespoke design but used tailwind for styling. charts are recharts. no dashboard lib.

[IneffablePigeon]

Baffled that there is now a fuel price API and yet there is no such electric charger price API

[fragmede]

Any appetite in adding data for electricity rates for EVs?

[theazureguy]

I would love too. But I have not found an API that surfaces this data. This data is only public as the CMA determined the market was fundamentally broken.

[rconti]

I can only go back to March 31?

[smashah]

https://petrol.now/trends has data since feb

[theazureguy]

yeah that's as far back as my data goes, started ingesting in march. no history existed before that

[rconti]

I see-- no problem, thank you. I thought it was just user error or a UI bug because of this comment:

> 90k records across 7,700 stations since January.

[NooneAtAll3]

what is "since January" about then?

[theazureguy]

data goes back to january but coverage is patchy early on as we were doing full fetches rather than continuous polling. march onwards is complete.

[umbra07]

Is at least part of this comment LLM-generated?

...

Just curious, not intending this as an attack on your project.

[theazureguy]

some of my replies yeah, been a bit busy keeping the site up while the thread was live. helps with the typos too.