Got the odd celebrity autograph gathering dust in your loft? It could be worth a fortune... though in some cases, it could be a forgery.

From royalty to rock stars, and from the living to the long-dead, these autographs of the rich and famous can sell for big money. 

Based on Paul Fraser Collectibles' PFC40 Autograph Index, read on to discover which autographs are worth the most money – and get the experts' top tips for ensuring that you never fall for a fake. All dollar amounts in US dollars, unless otherwise stated.

Let's start with the autographs of people who are still alive. A signed photograph of Vladimir Putin, much like the one pictured here from 2001, is worth around $115 (£100).

While $115 isn't to be sneezed at, it still marks a 50% decrease from the previous year, when the Russian President's autograph was valued at $237 (£200).

A signed photograph of the famously left-handed former US President is estimated to be worth around $688 (£600).

And that's just the start of Obama's paper-related money-makers. A handwritten letter that he penned to Jennifer Cline, a skin cancer patient who'd recently lost her job, sold for $7,000 (£5.4k) in 2010.

Meanwhile, pencil sketches – including self-portraits – that Obama drew on White House stationery also sold at auction, making $11,000 (£8k) in 2017. 

On to another former POTUS: Donald Trump's autograph is worth around $1,145 (£1k) according to the index data.

This is a 25% increase from 2021, when his signature was worth $916 (£800)

Beloved by fans around the world as the drummer from iconic 60s pop band the Beatles, Ringo Starr announced via video message in 2008 that he was going to stop signing memorabilia.

Now, the octogenarian's signature can fetch up to $2,000 (£1,750). 

According to the latest figures, Prince Harry's signature is worth $2,294 (£2k), which is a 33% increase from 2021.

Following his departure from the Royal Family in 2020, the value of Harry's autograph fell from $2,080 (£1,750) to $1,783 (£1,500).

As the author of the best-selling Harry Potter series, JK Rowling is used to signing books.

A copy of one of her magical tomes bearing her squiggle inside could fetch you as much as $3,443 (£3k).

Worth considerably more than that of his fellow former bandmate Ringo Starr, Sir Paul McCartney's signature is currently valued at $4,590 (£4k).

That's a 36% increase from 2021, when the autograph of the Beatles singer was worth $3.5k (£2,950).

He's first in line to the British throne and, according to the latest figures, the value of Prince William's signature is $4,590 (£4k).

That's a 14% increase from 2021, when the future monarch's autograph could sell for around $4.1k (£3,500).

While getting the autograph of a living celebrity can be lucrative, the real money is often to be found in the autographs of those who have already passed away.

Read on as we list the most valuable autographs of those who are no longer with us – and keep your eyes peeled for our tips to help you spot a fake...

The autograph of the late Nirvana frontman Kurt Cobain has increased in value by 14% between 2021 and 2022, and is currently worth a cool $4,590 (£4k).

Cobain would often misspell his own name, most likely for his own amusement, with one common variation being "Kurdt Cobain".

This quirky behaviour can mean that identifying the real deal is a challenge. Due to the increase in value of an autograph, the number of fakes available to buy online will also increase, so it's always best to do business with a reputable dealer.

Pictured: an authentic Kurt Cobain autograph. 

Elizabeth II’s autograph is worth a cool $6,879 (£6k).

The late monarch had the most valuable signature of any other living person before she passed away in September 2022, and only time will tell how this figure will change over the coming months and years.

Traditional protocol prevents the Royal Family from signing autographs publicly in a bid to prevent forgery, so a genuine autograph by the Queen (like the one shown here) is rare.

Signed photographs of the late monarch are particularly scarce. When looking out for a fake, bear in mind that Queen Elizabeth II rarely signed anything in public beyond official documents and Christmas cards. 

A signature from the late Disney entrepreneur could fetch you a cool $8,045 (£7k).

Unsurprisingly, autographs that are accompanied by a quick sketch of Disney's iconic Mickey Mouse character are particularly lucrative... 

Unfortunately, there are many bogus Walt Disney autographs for sale online and identifying a fake can be tricky.

For one thing, Walt Disney's authentic signature evolved over the decades, while the filmmaker was also prone to signing his name in both cursive and block print.

If you're unsure of an autograph's authenticity, it's always a safe bet to contact a specialist.

Of the four members of the Beatles, the late John Lennon's autograph is the most coveted.

A signed photograph of the bespectacled star has a rough value of $9,758 (£8.5k), which means it's enjoyed a 7% increase between 2021 and 2022.

Unscrupulous dealers have few qualms about selling fake John Lennon autographs to unsuspecting collectors, so it pays to swot up on the real deal.

This fake would be obvious to a collector, as the handwriting style is too angular to belong to the real Lennon, whose script was more "curvy".

JFK's signature is extremely collectable and, while there are many examples in existence, the vast majority of them are either autopenned or printed.

The rarer autographs are the ones that he signed by hand – and naturally, they're the ones that can attract the highest prices.

While fakes are one thing, looking out for autopenned (signatures created via a machine for speed) or printed signatures is something else that should be on your radar. 

Although they can still be valuable, the real deal can be worth a substantial amount more.

Autographs of rock or movie stars who died young can command premium prices, particularly if they're members of the infamous "27 Club".

Jimi Hendrix is no exception to the rule. A photograph bearing the signature of the Voodoo Child singer has a typical value of $10,312 (£9k) in 2022, according to the PFC40 Autograph Index.

However, Hendrix's autograph is one of the most commonly forged out there according to the PSA/DNA Autograph Report, which lists the most copied celebrity signatures.

On first inspection, this dubious example may look genuine, but the overly flamboyant capital "J" and uncharacteristic flow actually make it crystal-clear that it is, in fact, bogus. 

As well as serving as British Prime Minister during World War II, Winston Churchill was also a prolific writer and note-taker.

Many examples of Churchill's highly desirable signature exist, found in government documents and personal correspondence. The signature is worth $11,458 (£10k).

As a rule, it's wise to look out for handwritten letters or inscriptions rather than lone signatures – detailed documents like these are harder to fake.

And of course, another way to avoid a fake Churchill signature is to ensure that you only do business with reputable dealers. The example shown here was faked by Allan Formhals in Southampton, England.

Formhals, who had also forged signatures by the likes of Robert Louis Stevenson and JRR Tolkien, was sentenced to 10 months in prison back in 2012 for the crime.

Autographs of legendary musicians from the 1960s are much sought-after, with signed Rolling Stones memorabilia particularly valuable.

A signed photo of the band's original line-up is worth $11,454 (£10k) in 2022.

Bogus Rolling Stones autographs are all too common and, according to former bassist Bill Wyman, the band even used to imitate each other's signatures when signing piles of records or photos for fans.

Speaking to Rolling Stone (fitting, no?) in 2013, Wyman revealed: "There were stacks and stacks of books, programmes to be signed, and we just used to grab a bunch each and sign everybody’s name. It was the only way to do it, because you couldn’t pass this stuff around. You didn’t have time; you were on stage in ten minutes".

To avoid Rolling Stone fakes, do your homework and familiarise yourself with the band members' various signatures before making your purchase.

Neil Armstrong was the first person to walk on the moon and reportedly signed thousands of photos, letters, and cards during his lifetime.

While his autograph isn't exactly the rarest, collectors will still pay top dollar for the best examples. According to the PFC40 Autograph Index, Armstrong's signature is currently worth around $11.9k (£10k).

Neil Armstrong autographs are considered high risk and the web is littered with fakes.

The signature shown here is a prime example. Experts and amateurs with a keen eye will notice it lacks flow and "speed", while the pressure of the pen is too uniform. These are all tell-tale signs of a forgery.

Dubbed "the pinnacle of royal collectables", the average item autographed by Diana, Princess of Wales commands a premium price tag of around $13,741 (£12k).

Princess Diana had the sort of handwriting that graphologists describe as "curvy", with the attribute commonly regarded as a sign of a warm and affectionate nature.

A blatant forgery, the autograph shown here is too narrow and angular to be attributed to the late princess.

Authentic documents or photos that have been signed by Albert Einstein – who is arguably the most famous scientist of the 20th century – are always in demand.

The current value of an item that has been signed by Einstein is about $13,741 (£12k).

Einstein autograph expert Gregory J. Mallon advises potential collectors to pay close attention to a few key details when looking out for the scientist's signature. 

These include noting the "heaviness' of the script (Einstein had a light hand); the flow of the capital "E" at the start of his surname; and the break between the "i" and the "n". Authentic autographs tend to have a smaller space between these letters.

When she passed away suddenly at the age of 36 in 1962, Marilyn Monroe left behind a wealth of collectables, including many signed items.

On average, an autograph by the late starlet can fetch as much as $13,741 (£12k). 

Experts estimate that only around 24% of Marilyn Monroe autographs are genuine.

In fact, there are so many fakes floating around that even the experts can have trouble distinguishing the real autographs from the forgeries.

We've said it before and we'll say it again: unless you're really knowledgeable, only source your autographs from well-regarded dealers.

Martial arts legend Bruce Lee is a firm fan favourite, so memorabilia bearing his name can mean big business.

Autographs penned by the The Way of the Dragon star attract high prices, with a typical value of $13,741 (£12k) in 2022. Pictured is a good example of an authentic Bruce Lee autograph.

Sadly, fake Bruce Lee autographs are ten-a-penny. As with most forgeries, they tend to be a lot more affordable than the genuine article, so if something seems too good to be true, it probably is.

Another thing to watch out for is signed posters from Lee's 1972 movie The Way of the Dragon. Lee never signed any of these, so if you ever come across one you'll know it's 100% fake.

James Dean's brooding good looks, powerful acting, and untimely death in 1955 at the age of 24 have made him one of the foremost cultural icons of the 20th century.

Needless to say, authentic examples of the heartthrob's autograph, such as this inscribed photo, can be worth a small fortune. 

In fact, the PFC40 Autograph Index values his signature at $21.4k (£18k) in 2022.

Spotting a fake James Dean signature can be challenging, but it's worth noting that his autograph stayed pretty consistent throughout his short adult life, so use the authenticated autographs as a visual guide.

This signed poster features a rather blatant forgery. The slant is off, and the "J" and "D" are too small in relation to the other letters.

Stephen Hawking's signature is rare and therefore extremely valuable.

Due to his battle with motor neurone disease, the theoretical physicist was no longer able to write by the end of the 1970s. In the later years of his life, he would occasionally sign books with his fingerprint dipped in ink. 

The PFC40 Autograph Index estimates that a Hawking autograph is worth around $35.7k (£30k).

Identifying a fake can be challenging. The shaky nature of the A Brief History of Time author's handwriting means his autographs are inconsistent and tough to profile.

Due to the rarity of a Hawking autograph, business should only be done with reputable dealers. Pictured: a genuine thumbprint from Stephen Hawking. 

We've looked at the individual values of autographs from the likes of John Lennon and Paul McCartney. So how much would a group photo signed by all four of the Beatles be worth?

According to Paul Fraser Collectibles, a signed picture of the legendary rock band could make you the hefty sum of $36,658 (£32k). 

Experts predict that only 6% of Beatles autographs on the open market are authentic.

If you're interested in snapping up a genuine example of the Fab Four's signatures, study the authenticated versions and only buy from a reputable seller. You'll also want to be extra-cautious with signed album pages post-Sgt. Pepper's Lonely Hearts Club Band, as these tend to be the most copied.

Steve Jobs has the most valuable autograph of any person, dead or alive. A signature from the late Apple founder, who passed away in 2011, is worth an astonishing $57,319 (£50k) in 2022.

The real deal is rare, simply due to the fact that the tech mogul wasn't a fan of signing autographs.

The looping, whimsical script that Jobs wrote in, combined with his habit of not capitalising his first or last name, are two key things to look out for. Shown here is a genuine example of his signature.

It's not just autographs that can be bogus, read: fortune or fake: masterpieces on trial