The Cheapest Oven Costs the Most Per Cooking Function

Two ovens, two prices, one question: which one is actually the better deal. The Siemens iQ100 HB113FBS1 is 689 EUR and has 5 heating functions, so each function costs 137.80 EUR. The Siemens iQ500 HB579GBR3 is 939 EUR, 250 EUR more upfront, but it has 14 heating functions, so each one costs 67.07 EUR. Pay more, get a 51 percent better price per function. That is the opposite of what the sticker prices suggest, and it holds up across the wider catalog, not just this one pair.

Key takeaways:

• The Siemens iQ100 HB113FBS1 costs 137.80 EUR per heating function (689 EUR / 5 functions); the Siemens iQ500 HB579GBR3 costs 67.07 EUR per function (939 EUR / 14 functions), a 51 percent gap in the pricier oven’s favor.
• Among 15 built-in ovens that publish both price and heating-function count, the two cheapest by sticker price, the Siemens iQ300 HB571ABS3 (669 EUR) and the Siemens iQ100 HB113FBS1 (689 EUR), land at 133.80 and 137.80 EUR per function, the two worst per-function values in the set.
• Energy class does not explain the range: 12 of the 15 ovens are rated A+, spread across almost the entire 67.07 to 139.21 EUR-per-function span, so the label tells you nothing about this number.
• The Siemens iQ500 VB578D0S0 (2489 EUR, 10 functions, 248.90 EUR/fn) is excluded from the headline range and the chart below. At 89.6cm wide it is a larger combi-steam format, not a standard 59.4 to 60cm built-in oven, so its number is not comparable.

Why does the cheapest oven cost the most per function?

Fifteen built-in ovens in our database publish both a price and a heating-function count, the two fields you need for this comparison. Sort them by price and a pattern shows up immediately: the two lowest sticker prices, 669 EUR and 689 EUR, both belong to five-function ovens, and both land at the bottom of the value ranking, 133.80 and 137.80 EUR per function. Meanwhile the best per-function value in the whole set, the Siemens iQ500 HB579GBR3 at 67.07 EUR, sits at 939 EUR, a middling price, not the cheapest and not the priciest.

A reasonable explanation: building an oven at all costs money before you add a single cooking program. The cavity, the door and glass, the control board, the fan motor, that is largely fixed regardless of whether the oven ships with 5 modes or 14. A five-function oven and a fourteen-function oven from the same range often share most of that hardware; the difference is mainly software and a few extra heating elements or a grill circuit. Spread the fixed cost over five functions and each one is expensive. Spread it over fourteen and the same fixed cost gets divided further, so each function gets cheaper even as the total price climbs. Think of it like a pizza split between two people versus eight: the pizza costs more to make with more toppings, but each slice gets cheaper as more people share the base cost of the oven and the delivery. That is a plausible read of the data, not something Siemens or Bosch states as a design principle, so treat it as an explanation that fits the numbers rather than a confirmed mechanism.

Does a higher energy class explain the gap?

No, and this is worth ruling out explicitly because energy class is the label most shoppers check first. Twelve of the fifteen ovens here are rated A+ on the legacy ovens scale, and those twelve span nearly the entire range, from 67.07 EUR per function up to 139.21 EUR per function. A+ tells you nothing about how many functions your money buys. Three ovens in the table do not publish a class at all (N/A), and they sit in the middle of the range too, not at either extreme. If you want the fuller story on why oven energy labels still use the old A+++ to D scale instead of the newer A to G format that fridges, washing machines and dishwashers moved to, that is a separate question about labeling regulation, not about value per function.

Steam function is not the driver either. Only two ovens in this set have a steam function, the Bosch Serie 8 HSG7584B1 (94.74 EUR/fn) and the Bosch Serie 8 HSG7364B1 (111.86 EUR/fn). Both sit in the middle of the ranking, not at the cheap end or the expensive end, so steam capability is not what is pushing any oven to either extreme.

The full comparison, all 15 ovens

Oven	Price (EUR)	Heating functions	EUR per function	Steam function	Energy class
Siemens iQ500 HB579GBR3	939	14	67.07	No	A+
Siemens iQ700 HB774G1B1	1039	14	74.21	No	A+
Siemens iQ500 HB578GBS3	679	9	75.44	No	A+
Bosch Serie 8 HBG7341B1	1099	14	78.50	No	A+
Bosch Serie 8 CBG7341B1	1119	12	93.25	No	A+
Bosch Serie 8 HSG7584B1	2179	23	94.74	Yes	A+
Bosch Serie 8 HMG778NB1	2099	22	95.41	No	N/A
Bosch Series 8 HBG7784B1	1349	14	96.36	No	A+
Bosch Serie 8 CMG7241B1	1599	16	99.94	No	N/A
Bosch Serie 8 HMG776NB1	2049	20	102.45	No	N/A
Bosch Serie 8 HSG7364B1	2349	21	111.86	Yes	A+
Siemens iQ300 HB571ABS3	669	5	133.80	No	A+
Siemens iQ100 HB113FBS1	689	5	137.80	No	A
Siemens iQ700 HB778G9B1	1949	14	139.21	No	A+
Siemens iQ500 VB578D0S0*	2489	10	248.90	No	A+

*The VB578D0S0 is 89.6cm wide, a large built-in combi-steam oven, not a standard 59.4 to 60cm oven. Its 248.90 EUR per function is listed for completeness but should not be read against the other 14 rows; it is a different product format, not a bigger or worse version of the same thing.

The chart below charts the 14 standard-width ovens, ranked from best to worst per-function value, and leaves the VB578D0S0 out for the reason above.

How do you check this yourself before you buy?

Two numbers, one division. Find the price and the heating-function count on the manufacturer’s own data sheet or the EU energy label, then divide price by functions. That is the whole calculation behind every figure in this piece. It works for any two ovens you are choosing between, not just the ones in our database, and it takes less time than reading a single review.

It will not always favor the pricier oven. Somewhere past a certain point extra functions stop adding real cooking capability and start adding marketing checkboxes, a steam-clean mode you will use twice a year priced the same as a convection setting you will use weekly. The number does not tell you which functions you will actually use, only what each one costs on paper. Use it to catch the obvious trap, a cheap oven with few functions charging more per function than a pricier one with many, and then apply your own judgment about which of those functions you would actually cook with.

If you are comparing two specific models, the oven comparison tool puts full spec sheets side by side, including price and heating-function count, so you can run this division without opening two browser tabs. Worth noting: this analysis covers 15 of the 21 built-in ovens we track; six do not publish both price and heating-function count on their own listings, a normal gap in manufacturer data disclosure rather than a flaw in the comparison.

Before you pay a premium for a “premium” oven, or before you grab the cheapest one on the shelf, check the full oven range and do the division. The Siemens iQ500 HB579GBR3 is the standout on this metric; the Siemens iQ100 HB113FBS1 shows what the trap looks like from the inside, a genuinely lower price that buys you the least oven per euro in the set.