Now as tradition goes, if a man wants to propose to his beau, the engagement ring should cost two to three months’ wages… So what are the celebs spending on engagement rings these days?

10. Big spender, Ben Affleck, is set to appear in this list twice. Bagging spot number ten first, he spent an estimated $500,000 on the ring he used to propose to actress and producer girlfriend, Jennifer Garner (half the amount he spent on the ring he gave to J-Lo…).

9. When French pro-basketball player Tony Parker took the plunge and decided to propose to Desperate Housewives star Eva Longoria, he commissioned renowned jeweller, Jean Dousset, to create a unique emerald-cut diamond ring that is thought to have cost more than $500,000.

8. The radiant-cut, yellow-diamond engagement ring on the finger of Brooke Mueller was put there by cheeky chappy Charlie Sheen – a ring that is reported to have cost over £550,000.

7. When Prince Charles proposed to Camilla Parker on bended knee, he was holding one of the most exquisite square-cut-diamond and white gold engagement rings in the celebosphere… Once owned by the Queen Mother, this Art-Decoera ring is estimated to be worth a cool million.

6. Ben Affleck’s proposal to J-Lo back in the mid-noughties saw him give her the gift of a 6.1-carat pink diamond, Harry Winston engagement ring worth $1.2 million.

5. Katie Holmes’ huge Edwardian-style, 5-carat, oval-shaped diamond engagement ring set in platinum and rose gold was her gift from now-husband, Tom Cruise. The unusual setting spices up the antique-styling, and this ring, rumoured to have cost over $1.5 million, is just a perfect example of how antique-inspired rose gold and platinum engagement rings should look.

4. When Michael Douglas asked Welsh actress Catherine Zeta-Jones to marry him, he gave her a 10-carat, marquise-cut antique diamond engagement ring with a value said to be more than $2 Million.

3. When Jacqueline Kennedy-Onassis’ 40-carat diamond ring, given to her by second husband Aristotle Onassis, was auctioned off for $2.6 million way back in 1996, it became the third most expensive engagement ring in history.

2. Back in 2004, billionaire business tycoon Donald Trump’s engagement gift to fiancée Melania Knauss was a 15-carat diamond ring. It was, for a time, the most expensive engagement ring and the most impressive one in history, as historical gemstone rings go. And then…

1. Paris Hilton’s 24-carat emerald-cut diamond ring was her engagement gift from Greek shipping heir, Paris Latis. However, while the grand gesture was worth a staggering $4.7 million, it appeared to be just that as the engagement lasted a mere four months and Hilton consequently auctioned the luxury trinket off for charity.

Right then chaps. At long last, you’ve decided to man up and ask your girlfriend for her fair hand in marriage – you’re going to pop the question. Now if, like most men, you’re not entirely au fait with the size of your beloved’s fingers, then you’re probably going to be struggling a bit when it comes to finding her perfect engagement ring. But fear not, because here’s a lowdown of the top five tricks that’ll help you find out without her smelling a rat.

Oh, and one vital point to note – with all of these ring-sizing methods, make doubly sure it’s the fourth finger of the left hand you’re getting the measurements for – remember, all fingers are different.

1. Use a ring sizer

Our very favourite and the most failsafe way of getting an accurate ring size measurement, you can use one of our free purpose-made ring sizers, which use the British standard (A-Z) for each 1.25mm of ring circumference with half sizes in between, and can be sent out in the post to you today, no less!

2. Enlist a friend’s help

Contact one of your beau’s trusted friends or close family members to help you pick out the engagement and wedding rings. They may well have previously got her a ring as a Christmas or birthday present, and may well already know the information you now need to. Alternatively, you could appeal to them for their help in stealthily acquiring one of her rings long enough to get in touch with an expert online jeweller for advice, or even innocently asking to try one of her rings on themselves to see if it matches.

3. Sneak a ring away to measure it while she’s not looking

If you can manage to acquire one of your girlfriend’s rings (fourth finger, left hand), you can use one of our ring sizers to measure it and contact us for expert advice. It’s vital, however, that you know for sure that the ring you’ve temporarily spirited away fits her absolutely perfectly – many girls often settle for and put up with a slightly off ring-measurement in order to be able to still wear a ring they really love. If she doesn’t wear your chosen ring on the correct finger, you and your online jeweller could probably make an educated guess based on which finger she does wear it on, but be braced for the possibility of having to get the ring resized – which can be extremely difficult or even impossible to do with diamond engagement rings, especially ones that feature an abundance of stones on the band.

However. If, for example, you’re unable to smuggle your girlfriend’s ring out of the house without her clocking it’s gone AWOL, then there are a couple things you can do to get around this – although bear in mind that these methods can subject to human error, and aren’t as advisable as using an alternative method that involves getting a precise measurement with our free ring sizer.

4. Measure a ring on your own finger

Try the ring on one of your own fingers and make a mark on your finger where it stops. Then, contact your online jeweller will be able to deduce her ring size by the width of your finger at the mark.

5. Make an impression of an existing ring

Make an impression of her ring in a bar of soap, blue sticking putty or clay (basically anything soft that will hold the shape that you impress into it), measure it using our free ring sizer and call for advice from an expert jeweller.

And finally…

Here’s a handy ring sizing chart that you can use to convert ring sizes from other global regions – this will save you the hassle of having to go down to your local high street to convert the measurement for you!