In Jainism, time (kāla) is discussed in two ways:

1. Empirical / practical time — the units used for measurement in worldly life.
2. Cosmic time-cycle — the immense cycles of utsarpiṇī and avasarpiṇī, each made of vast ages. ( jainknowledge.com)

Smallest to bigger units

The commonly given ladder of time-units begins like this:

• Samaya — the smallest indivisible unit of time. ( jainknowledge.com)
• Āvalikā / Avali — a very tiny unit made of innumerable samayas. Different texts/traditions use this as the next step after samaya. ( jainknowledge.com)
• Ucchvāsa / Niśvāsa — an inhalation or exhalation; some texts define “one breath” as one ucchvāsa plus one niśvāsa. ( jainqq.org)
• Prāṇa
• Stoka
• Lava
• Nālikā / Ghari
• Muhūrta
• Ahorātra — day and night
• Pakṣa — fortnight
• Māsa — month
• Ṛtu — season
• Āyana — half-year
• Varṣa / Saṃvatsara — year
• then larger traditional units such as yuga, śatābdī, sahasrābdī, lakṣābdī, pūrvāṅga, pūrva, and then the vast Jain cosmic units like palyopama and sāgaropama. ( jainqq.org)

Mathematical checks

1) Muhūrta

A very standard Jain definition is:

• 30 muhūrtas = 1 day and night (ahorātra)
• so 1 muhūrta = 48 minutes. ( jainqq.org)

This is mathematically correct because:

• 24 hours = 1440 minutes
• 1440 ÷ 30 = 48 minutes

2) Ahorātra

• 30 muhūrtas = 1 ahorātra
• therefore 1 ahorātra = 24 hours. ( jainqq.org)

3) Month, year, and larger human-scale units

One common Jain sequence is:

• 15 ahorātras = 1 pakṣa
• 2 pakṣas = 1 māsa
• 2 māsas = 1 ṛtu
• 3 ṛtus = 1 āyana
• 2 āyanas = 1 varṣa. ( jainqq.org)

This means the system is internally consistent:

• 15 days × 2 = 30 days per month
• 2 months per season
• 3 seasons per half-year
• 2 half-years per year. ( jainqq.org)

4) Higher traditional counts

One source gives the following chain:

• 5 varṣa = 1 yuga
• 20 yuga = 1 śatābdī
• 10 śatābdī = 1 sahasrābdī
• 10,000 years = 1 lakṣābdī
• 84 × 10⁵ years = 1 pūrvāṅga
• and then much larger units follow. ( jainqq.org)

Another source gives the cosmic-scale hierarchy up to palyopama, sāgaropama, and the huge half-cycles of Jain time. ( jainelibrary.org)

Scriptural-style analogies

Jain texts and later Jain expositions use vivid analogies to help explain the vast scale:

• Samaya is said to be the tiniest indivisible instant, smaller than anything we use in ordinary life. ( jainknowledge.com)
• Āvalikā is often explained in relation to a blink of the eye or a tiny perceptible interval. ( jainqq.org)
• Muhūrta is the practical human unit, equal to 48 minutes, used for daily religious and worldly calculations. ( jainqq.org)
• Palyopama and sāgaropama are the classic Jain “ocean-like” immense units, used to express the unimaginable duration of cosmic ages. ( jainqq.org)

A simple ladder

A practical way to remember the scale is:

samaya → āvalikā → breath-based units → lava → nālikā/ghari → muhūrta → ahorātra → pakṣa → māsa → ṛtu → āyana → varṣa → yuga → larger cosmic units → palyopama → sāgaropama → utsarpiṇī/avasarpiṇī

Important note

Different Jain texts and traditions sometimes differ in the naming or exact intermediate count of some very small units like āvaili/āvalikā, ucchvāsa, prāṇa, stoka, lava. But the core structure is stable: samaya is the smallest, muhūrta is 48 minutes, and the higher units expand into vast cosmic time. ( jainknowledge.com)

If you want, I can also give this as a clean table from samaya to sāgaropama with the numerical conversions in one place.