Factor |
SI prefix |
Value |
Item
|
0
|
|
1.0×10−
|
Almost never.
|
10−4.5×1029
|
|
10−4.5×1029
|
Probability of a human spontaneously teleporting 50 kilometres (31 miles) due to quantum effects[1]
|
10−360,783
|
|
1.0×10−360,783
|
Probability of a monkey in front of a typewriter typing Hamlet on the first try, taking punctuation, capitalization and spacing into account[2]
|
10−183,800
|
|
1.0×10−183,800
|
Rough first estimate of the probability of a monkey in front of a typewriter typing all the letters of Hamlet on the first try[3]
|
10−67
|
|
8.07×10−67
|
Probability of shuffling a standard 52-card deck in any specific order[4]
|
10−30
|
Quecto- (q)
|
1×10−30
|
One in 1,000,000,000,000,000,000,000,000,000,000
|
10−28
|
|
4.47×10−28
|
Approximate probability of all four players in a game of bridge getting a complete suit[5]
|
10−27
|
Ronto- (r)
|
1×10−27
|
One in 1,000,000,000,000,000,000,000,000,000
|
10−24
|
Yocto- (y)
|
1×10−24
|
One in 1,000,000,000,000,000,000,000,000
|
10−21
|
Zepto- (z)
|
1×10−21
|
One in 1,000,000,000,000,000,000,000
|
10−19
|
|
2.83×10−19
|
Approximate probability of matching 20 numbers for 20 in a game of keno
|
10−18
|
Atto- (a)
|
1×10−18
|
One in 1,000,000,000,000,000,000
|
10−16
|
|
2.74×10−16
|
Probability of rolling snake eyes 10 times in a row on a pair of fair dice
|
10−15
|
Femto- (f)
|
1×10−15
|
One in 1,000,000,000,000,000
|
10−12
|
Pico- (p)
|
1×10−12
|
One in 1,000,000,000,000
|
10−11
|
|
2.52×10−11
|
Approximate probability of one player in a game of bridge getting a complete suit
|
10−10
|
|
2.0×10−10 |
Probability per second of a SATA harddisk failure during an MTBF test[6]
|
5.25×10−10 |
Caesium-137 atom decay each second[7]
|
9.9×10−10 |
Gaussian distribution: probability of a value being more than 6 standard deviations from the mean on a specific side[8]
|
10−9
|
Nano- (n)
|
1×10−9
|
One in 1,000,000,000
|
3.9×10−9 |
Probability of an entry winning the jackpot in the Mega Millions multi-state lottery in the United States*[9]
|
5.707×10−9
|
Probability of winning the Grand Prize (matching all 6 numbers) in the US Powerball lottery with one ticket in January 2014
|
10−8
|
|
1.303×10−8
|
Probability of winning the Grand Prize (matching all 6 numbers) in the Australian Powerball lottery with one ticket in March 2013
|
2.219×10−8
|
odds of winning the Jackpot (matching the 6 main numbers from 59) in the UK National Lottery with one ticket since 10 October 2015
|
7.151×10−8
|
odds of winning the Jackpot (matching the 6 main numbers from 49) in the UK National Lottery with one ticket until 10 October 2015
|
10−7
|
|
1.17×10−7 |
Death per aircraft journey[10]
|
2.9×10−7 |
Gaussian distribution: probability of a value being more than 5 standard deviations from the mean on a specific side[11]
|
8.0×10−7 |
Death per person per year by lightning strike in Germany (Europe)[12]
|
10−6
|
Micro- (μ) |
1×10−6 |
Life-threatening adverse reaction from a measles vaccine[13]
|
1.43×10−6
|
Probability of the Yellowstone supervolcano erupting in a given year.
|
1.5×10−6
|
Probability of being dealt a royal flush in poker
|
10−5
|
|
1.4×10−5
|
Probability of being dealt a straight flush (other than a royal flush) in poker
|
1.6×10−5 |
Risk that the asteroid 2013 TV135 which is 450 meters wide[14] will impact earth in 2032[15]
|
3.2×10−5 |
Gaussian distribution: probability of a value being more than 4 standard deviations from the mean on a specific side[16]
|
8.43×10−5 |
Probability of a deadly vehicle accident per person in Europe each year (not including former Yugoslavia)[citation needed][when?]
|
10−4
|
|
2.4×10−4
|
Probability of being dealt a four of a kind in poker
|
10−3
|
Milli- (m) |
1.3×10−3 |
Gaussian distribution: probability of a value being more than 3 standard deviations from the mean on a specific side[17]
|
1.4×10−3 |
Probability of a human birth giving triplets or higher-order multiples[18]
|
Probability of being dealt a full house in poker
|
1.9×10−3
|
Probability of being dealt a flush in poker
|
2.7×10−3
|
Probability of a random day of the year being your birthday (for all birthdays besides Feb. 29)
|
4×10−3
|
Probability of being dealt a straight in poker
|
10−2
|
Centi- (c)
|
1.8×10−2
|
Probability of winning any prize in the UK National Lottery with one ticket in 2003
|
2.1×10−2
|
Probability of being dealt a three of a kind in poker
|
2.3×10−2 |
Gaussian distribution: probability of a value being more than 2 standard deviations from the mean on a specific side[17]
|
2.7×10−2
|
Probability of winning any prize in the Powerball with one ticket in 2006
|
3.3×10−2 |
Probability of a human giving birth to twins[19]
|
4.8×10−2
|
Probability of being dealt a two pair in poker
|
10−1
|
Deci- (d) |
1.6×10−1 |
Gaussian distribution: probability of a value being more than 1 standard deviation from the mean on a specific side[20]
|
1.7×10−1 |
Chance of rolling a '6' on a six-sided die
|
4.2×10−1
|
Probability of being dealt only one pair in poker
|
5.0×10−1 |
Chance of getting a 'head' in a coin toss. Physically less than 0.5; approximately 4.9983×10−1 for US nickel accounting for 1.67×10−4 (1-in-6000 chance) of coin landing on its edge.[21]
|
Probability of being dealt no pair in poker
|
100
|
|
1×100
|
Certain
|