Experts estimated the cost of Pippa Middleton's wedding, and... woah.

It’s no secret weddings are expensive. But when you’re the sister of the future Queen, you can bet you’ll be spending more on your big day than what most women accumulate in super. In a lifetime.

Wedding planning app Bridebrook has done the maths to bring us the expected cost of Pippa Middleton’s wedding to hedge fund millionaire fiance, James Matthews.

Watch: What’s the craziest thing a bridezilla has made you do for their wedding? (post continues after video…)

OK, so here we go.

Taking into consideration everything from the dress to the table decorations, the app predicts the total cost of Pippa’s wedding to sit roughly around the AUD$435,000 mark. Yep.

No, that’s not a rogue four. Or zeros. The estimated amount, which is a lot (but not enough to buy a house in 2017, mind you) is 15 times the average cost of average people weddings.

And what might one spend more than $400K on, you ask? Here are some key parts of Bridebrook’s breakdown:

The dress and veil: Just over $17,500 on a rumoured Giles Deacon couture number, set off with a $3500 designer veil.

Hair and makeup: To get the same glam squad as sister Kate had for her big day, it’ll set Pippa back around $3000.

Bridesmaids, flower girls and page boys outfits: Depending on how many bridesmaids Pippa has, fitting out the bridal party could cost up to $4,000. As for any children involved in the proceedings, adorable outfits made by the same designer as the royal wedding's are estimated to cost between $300 and $600 a pop. Ouch.

Wedding rings: The Cartier rings, diamond encrusted for her and a masculine platinum band for him, are estimated to cost the couple $27,000 and $2,500 respectively.

Venue, catering and flowers: You'd think holding the wedding at home would cut costs, but catering for over 350 guests in royal style doesn't come cheap. All up, you're looking at $114,000 for decking out the venue, $123,000 to feed the masses and $28,000 for the flowers.

Listen: Mamamia Out Loud talk the extreme costs of weddings (post continues after audio...)

Other expenses include: the cake ($4,500), a bar and dancefloor where Wills can bust out some Dad moves ($6,000), entertainment ($14,000), a videographer to capture the day ($7,000) and wedding stationary and favours ($10,200). And don't forget the, ahem, facilities. Even rich people have to break the seal sometime.

Let's all take a moment to imagine a life where money is no object...

How much is too much to spend on a wedding?