What is the format used for trading symbol to get corresponding instrument key ? BANKNIFTY23N3043600PE dosnt work

for example BANKNIFTY23N2243600PE is symbol for nov 22nd expiry , how can i find nov 30th expiry on complete instrument key csv?
BANKNIFTY23N2243600PE works
BANKNIFTY23N3043600PE is not working
BANKNIFTY23D0643600PE works
BANKNIFTY23D1343600PE works
Please help

Hi @Ashok_Kumar_k

To anwer your query, 30th Nov is a monthly expiry so you would not get weekly expiry contract for the same

Below is the variation between monthly and weekly contracts, we will get a note added in the documentation as well

BANKNIFTY 23NOV 36500 CE → yyMMM

BANKNIFTY 23N22 36500 CE → yyMdd

If you see the first contract, it is the one you are looking for with 23NOV as the keyword whereas for other dates, you will get the weekly comtract with 23N22 keyword

Hope this helps.

@AbhishekRathore ,

Perfect , that makes sense, Thanks for resolving .

Hello @AbhishekRathore this format dosnt work for next year contracts ,
Example BANKNIFTY24J1748000CE Dosnt work ,
is the format changed ? whats the format to get Jan17th expiry on FNO?

The contract format may be altered by the exchange without prior notification to the broker.

It appears that the new weekly contract format replaces month names with numeric values, as seen below:

Old Format: BANKNIFTY-24-J-17-48000-CE
New Format: BANKNIFTY-24-1-1748000-CE

This modification in format has been noted in Nifty and other contracts as well. We plan to verify this with the exchange for confirmation, but it currently looks like the format has changed.

This is another reason why we depend on instrument keys, ensuring that any unannounced changes do not impact our system and our customers.