KALCHAKRA Jains believe that time is infinite, without any beginning or end. Time is divided into infinite equal time cycles (Kalchakras). Every time cycle is further sub-divided in two equal halves. The first half is the progressive cycle or ascending order, called Utsarpini. The other half is the regressive cycle or the descending order, called Avasarpini. Every Utsarpini and Avasarpini is divided into six unequal periods called eras. During the Utsarpini half cycle, progress, development, happiness, strength, age, body, religious trends, etc. go from the worst conditions to the best. During the Avasarpini half cycle, progress, development, happiness, strength, age, body, religious trends, etc. go from the best conditions to the worst. Presently, we are in the fifth Ara of the Avasarpini phase. When the Avasarpini phase ends the Utsarpini phase begins. This kaalchakra repeats again and continues forever.
The six aras are:
(1) Sukham Sukham Kal (very good).
(2) Sukham Kal (good).
(3) Sukham Dukham Kal (good bad).
(4) Dukham Sukham Kal (bad good).
(5) Dukham Kal (bad).
(6) Dukham Dukham Kal (very bad).
1) Sukham Sukham Kal: This is a time of absolute happiness. During this phase people are very tall and live for a very long period of time. Children are born as twins, a boy and a girl. All the needs and desires of the people are fulfilled by ten different kinds of Kalpavriksha (wish-giving trees). The trees provide places to live, clothes, pots and pans, good food, fruits and sweets, harmonious music, jewelry, beautiful flowers, radiant lamps, and a bright light at night. There is no killing, crime, or vice.
2) Sukham Kal - This is the phase of happiness, but it is not absolute. The wish-giving trees still continue to provide for the peopoles needs, but the people are not as tall and do not live as long.
3) Sukham Dukham Kal - This is a phase consisting of more happiness than misery. During this period the kalpvrikshas do not consistently provide what is desired. Towards the end of this period in the current time cycle Rushabhdev became the first Tirthankar. He realized that things were going to get worse. So he taught the people useful arts including, sewing, farming, and cooking which will enable them to depend upon themselves. He also introduced a political system and became the first king. This era came to an end three years and eight months after the nirvana of Rushabhdev. The first Chakravarti Bharat, Bahubali also known for his strength, and Brahmi who devised eighteen different alphabets were Rushabhdevas children.
4) Dukham Sukham Kal - This is a phase of more misery, sorrow, and suffering than happiness. The other twenty-three Tirthankaras and eleven Chakravarties were born during this era which came to an end three years and eight months after Lord Mahavir's nirvan.
5) Dukham Kal - This ara is currently prevailing. It is an ara of unhappiness which began a little over 2,500 years ago and will last for a total of 21,000 years. No one born during this period will gain salvation in their present life, because no one will observe true religion. It is said that by the end of this ara, the Jain religion will be lost.
6) Dukham Dukham Kal - This is a time of absolute misery and unhappiness. During this time people will experience nothing but suffering. There will be no trace of religious activities. The life spans of people will be very short, exceeding no more than twenty years. Most people will be non-vegetarian and the social structure will be destroyed. The weather will become extreme, the days will be very hot, and the nights will be very cold. At the end of this ara, a period of Utsarpini will start and the time wheel will take an upward swing. There will be days of rain which will provide nourishment so that seeds can once again grow. Miseries will diminish and happiness will increase until absolute happiness is once again reached.
The changes in living being and non living substances (from one paryay to another paryay of a substance) are measured in the units of time. However time is not the cause of such changes. There are two views exist in Jainism with regards to time.
1. Time is an imaginary thing; it has no real existence.
2. Time has a real existence consisting of innumerable time atoms.
The smallest indivisible portion of time is called Samaya. Combination of samayas are called moment, second, minute, hour, day, month, year, etc. Innumerable samayas One avali (time required to blink a eye)
16,777,216 avalis One muhurt (48 minutes)
30 muhurts One day
15 days One fortnight
2 fortnights One month
12 months One year
5 Years One Yuga
8,400,000 x 8,400,000 years One Purva (70,560,000,000,000 Years)
Innumerable years One palyopama*
10 x 10,000,000 x 10,000,000 Palyopamas One Sagaropama
10 x 10,000,000 x 10,000,000 Sagaropams Avasarpini or Utsarpini (Half Cycle)
20 x 10,000,000 x 10,000,000 Sagaropams One Time Cycle*One Palyopama = The time required to empty Sixty Four cubic Gau (512 cubic miles) deep well completely filled with hairs of a seven day old newly born baby and one hair is removed every 100 years.
Time is a continuous Cycle of Decline Era (Avasarpini kal) and Rise Era (Utasarpini kal). During declining era, human virtues, natural conditions decline over the time, while during rising era, improve over the time.
Each era is divided into six parts. The duration and the name of its part is defined as follows:
Six parts of Declining Era (Avasarpini) Time Cycle
1. Happy_happy 4 x 10E14 Sagaropams
2. Happy 3 x 10E14 Sagaropams
3. Happy_unhappy 2 x 10E14 Sagaropams
4. Unhappy_happy 1 x 10E14 Sagaropams - 42000 years
5. Unhappy 21000 years (present Era passed @2500years)
6. Unhappy_unhappy 21000 years

Six parts of Rising Era (Utsarpini) Time Cycle
1. Unhappy_unhappy 21000 years
2. Unhappy 21000 years
3. Unhappy_happy 1 x 10E14 Sagaropams - 42000 years
4. Happy_unhappy 2 x 10E14 Sagaropams
5. Happy 3 x 10E14 Sagaropams
6. Happy_happy 4 x 10E14 Sagaropams