fynxIQ
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The checks, one at a time, for nothing.

Each tool is one piece of what fynxIQ runs on every return. The ones that read files do it in your browser: nothing you drop or type is uploaded.

01Reads files

GSTR-1 from marketplace reports

Drop a month of Amazon, Flipkart, Meesho or Myntra files and see the return and every check, worked out in your browser.

MTR_B2C-JULY-2026.csv1 blocker
Drop a file
02Reads files

GSTR-1 JSON validator

Hold a JSON from any product against the offline tool’s rules and the Table 12 cross-tally before you upload it.

GSTR-1-072026.json2 refused
Drop a file
03Checker

HSN code checker

Whether a code can exist, how many digits Table 12 needs from you, and the rate on file, with what is not known said plainly.

71170990Refused
Open the tool
04Calculator

GST late fee calculator

The late fee on a GSTR-1, GSTR-3B, GSTR-4, GSTR-7 or GSTR-8 from the due date and the filing date, with the caps in force and the three-year bar.

GSTR-3B · 3 days late₹150.00
Open the tool
05Calculator

TCS calculator for sellers

What a marketplace should collect under section 52 on a month’s net sales, by tax head, against what the portal shows.

₹8,00,000.00 net sales₹4,000.00
Open the tool
06Checker

GSTIN checker

Whether a GSTIN is well formed and its check digit matches, with the state and PAN it carries.

29DEMOA1234A1Z4Karnataka
Check GSTIN
0files uploaded by these tools. They are read in your browser and gone when you close the tab.
6tools, each one piece of the checks fynxIQ runs on every return.
₹0.00to use them. No sign-up, no email, no limit on how often.
In the app

The rest of the month, on every plan.

Each is on the free plan too: 2 GSTINs and 6 prepared returns a month, with every check.

What it does, in full
GSTR-1GSTR-1 from any sales fileMarketplaces, registers, bill books and Tally in one JSONBillsBills and invoices from photos and PDFsRead, checked by arithmetic, confirmed by youGSTR-2BGSTR-2B against your purchase booksWhich credit you can claim, bill by billGSTR-3BGSTR-3B draftFrom the GSTR-1 and GSTR-2B, held against the portal’sTCSTCS statement checkEach marketplace’s TCS against your salesTallyTally, both waysA Day Book in; sales and purchases outCA firmsBoard, calendar and upload links, for CA firmsEvery client’s month, and what falls due

Do the whole month in fynxIQ.

Free for 2 GSTINs and 6 prepared returns a month. No card is asked for.

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