Orders of magnitude (time)

Seconds

Orders of magnitude (time)

Factor (s)	Multiple	common units	orders of magnitude
10−43		Planck time, the shortest physically meaningful interval of time, and consequently the youngest the known universe can be measured. ≈ 5.4×10−43 s	10−43 s
10−24	1 yoctosecond	1 ys, time for top quark decay, 91 ys, half-life of lithium-4	1 ys and less, 10 ys, 100 ys
10−21	1 zeptosecond	7 zs: half-life of helium-9's outer neutron in the second nuclear halo. About 17 zs: the approximate period of electromagnetic radiation at the boundary between gamma rays and X-rays. About 300 zs: typical cycle time of X-rays, on the boundary between hard and soft X-rays	1 zs, 10 zs, 100 zs
10−18	1 attosecond	The current shortest measurable period of time (as of February 2004) is 100 attoseconds.	1 as, 10 as, 100 as
10−15	1 femtosecond	cycle time for 390 nanometre light, transition from visible light to ultraviolet	1 fs, 10 fs, 100 fs
10−12	1 picosecond	half-life of a bottom quark	1 ps, 10 ps, 100 ps
10−9	1 nanosecond	Time to execute one instruction in a personal computer; light travels 12 inches second = 1000000000 nanosecond	1 ns, 10 ns, 100 ns
10−6	1 microsecond	sometimes abbreviated as "µs" or "µsec"	1 µs, 10 µs, 100 µs
10−3	1 millisecond	blink of an eye ~ 50 to 80 ms	1 ms, 10 ms, 100 ms
100	1 second	minute = 60 s	1 s, 10 s, 100 s
103	1 kilosecond (16.7 minutes)	hour = 3600 s day = 86 400 s = 86.4 ks week = 604.8 ks	103 s, 104 s, 105 s
106	1 megasecond (11.6 days)	month = 2.6 x 106 s year = 31.6 Ms = 107.50 s ≈ π x 107 s	106 s, 107 s, 108 s
109	1 gigasecond (32 years)	century = 3.16 Gs ≈ π×109 s millennium = 31.6 Gs ≈ π×1010 s	109 s, 1010 s, 1011 s
1012	1 terasecond (32 000 years)	eon = 31.6 Ts ≈ π×1013 s	1012 s, 1013 s, 1014 s
1015	1 petasecond (32 million years)	aeon = 31.6 Ps ≈ π×1016 s 4.3×1017 s ≈ 13.7 billion years, the approximate age of the universe	1015 s, 1016 s, 1017 s
1018	1 exasecond (32 billion years)	--	1018 s, 1019 s, 1020 s
1021	1 zettasecond (32 trillion years)	--	1021 s, 1022 s, 1023 s
1024	1 yottasecond (32 quadrillion years)	--	1024 s, 1025 s, 1026 s and more

Years

Orders of magnitude (time)

Factor (a)	Multiple	common units	orders of magnitude
10−50		Planck time, the shortest physically meaningful interval of time ≈ 1.71×10−50 a	10−50 a
10−24	1 yocto-annum	--	1 ya and less, 10 ya, 100 ya
10−21	1 zepto-annum	--	1 za, 10 za, 100 za
10−18	1 atto-annum	--	1 aa, 10 aa, 100 aa
10−15	1 femto-annum	--	1 fa, 10 fa, 100 fa
10−12	1 pico-annum	--	1 pa, 10 pa, 100 pa
10−9	1 nano-annum	1 second = 3.17 × 10-8 a ≈ 10-7.50 a	1 na, 10 na, 100 na
10−6	1 micro-annum	1 minute = 1.90 × 10-6 a 1 hour = 1.40 × 10-4 a	1 ua, 10 ua, 100 ua
10−3	1 milli-annum	1 day = 2.73 × 10-3 a 1 week = 1.91 × 10-2 a	1 ma, 10 ma, 100 ma
100	1 annum	year = 1 annum decade = 10 anna century = 100 anna	1 a, 10 a, 100 a
103	1 kilo-annum	millennium = 1000 anna	103 a, 104 a, 105 a
106	1 mega-annum	epoch = 1,000,000 anna	106 a, 107 a, 108 a
109	1 giga-annum	aeon = 1,000,000,000 anna 1.37×1010 a ≈ 13.7 billion years, the approximate age of the universe	109 a, 1010 a, 1011 a
1012	1 tera-annum	---	1012 a, 1013 a, 1014 a
1015	1 peta-annum	---	1015 a, 1016 a, 1017 a
1018	1 exa-annum	--	1018 a, 1019 a, 1020 a
1021	1 zetta-annum	--	1021 a, 1022 a, 1023 a
1024	1 yotta-annum	--	1024 a, 1025 a, 1026 and more

The pages linked in the right-hand column contain lists of times that are of the same order of magnitude (power of ten). Rows in the table represent increasing powers of a thousand (3 orders of magnitude).

Conversion from year to second is year × 31 557 600 using the Julian year. Conversion from $\log _{10}year$ to $\log _{10}second$ is approximately $\log _{10}year+7.50$. Example conversion; $1year=10^{0}year=10^{0+7.50}seconds=10^{0.50+7}s=3.16*10^{7}s$.

See also

• Natural history
• Geologic timescale
• Human timescales
• Logarithmic timeline
• Timeline of evolution
• Timeline of the Big Bang

• units
• Planck units
• Wikipedia:size comparisons

• second
• annum