Hii May I get Jee mains Syllabus of 2020 January?If weightage available please let me know that.

Dear candidate here's the detailed syllabus for JEE MAINS January session :-
Mathematics
Complex numbers and quadratic equations
Matrices and determinants
Sets, relations and functions
Mathematical induction
Permutations and combinations
Mathematical reasoning
Limit, continuity and differentiability
Integral calculus
Three-dimensional geometry
Differential equations
Binomial theorem and its simple applications
Sequences and series
Vector algebra
Statistics and probability
Trigonometry
Co-ordinate geometry

Physics

Section A
Physics and measurement
Rotational motion
Thermodynamics
Kinematics
Work, energy and power
Properties of solids and liquids
Gravitation
Laws of motion
Oscillations and waves
Electronic devices
Kinetic theory of gases
Current electricity
Communication systems
Electromagnetic induction and alternating currents
Magnetic effects of current and magnetism
Optics
Electromagnetic waves
Atoms and nuclei
Electrostatics
Dual nature of matter and radiation

Section B
Experimental Skills

Chemistry

Physical Chemistry
Some basic concepts in chemistry
States of matter
Atomic structure
Chemical bonding and molecular structure
Chemical thermodynamics
Solutions
Equilibrium
Redox reactions and electrochemistry
Chemical kinetics
Surface chemistry

Organic Chemistry
Purification and characterisation of organic compounds
Hydrocarbons
Chemistry in everyday life
Principles related to practical chemistry
Organic compounds containing halogens
Organic compounds containing oxygen
Organic compounds containing nitrogen
Polymers
Some basic principles of organic chemistry
Biomolecules

Inorganic Chemistry
Classification of elements and periodicity in properties
Hydrogen
Block elements (alkali and alkaline earth metals)
P Block elements group 13 to group 18 elements
d- and f - block elements
Co-ordination compounds
Environmental chemistry
General principles and processes of isolation of metals
You can check this link for topic wise Weightage
All the best
Hope this helps