It started with a return that did not add up.

We sell on four marketplaces and file our own GST. One month we looked back at a GSTR-1 we had already filed. Its HSN summary did not equal its sales. The portal had accepted it anyway.

Nothing in the process had said so. A free tool had turned the marketplace exports into a JSON, the JSON was valid, and the portal took it. Table 12 carried ₹580.58 of taxable value against ₹3,614.45 in the tables it summarises: the whole consumer half of the month was missing. Every total looked right on its own; only the tables held against each other showed it.

fynxIQ is what came out of that: a tool that reads each marketplace’s file by rules written for it, puts every row in one ledger with its source, builds the returns from that ledger, and then tries hard to prove them wrong. Tables that do not agree are a blocker. Doubt is a warning. Nothing is averaged away.

It is built by the team behind ListIQ, used by 50,000+ sellers in India. We still file our own GST on it every month.

Raunak Pathak is the founder, and writes the guides on this site. LinkedIn

What we will not change.