RealValue FX Engine
Calculate exactly how much USD you get for your INR — including forex spread, GST (Rule 32), and TCS — and keep a searchable, browser-only log of every FX transaction.
About RealValue FX Engine
RealValue FX Engine tells you exactly how many dollars your rupees buy — after the bank’s hidden charges, GST, and TCS.
Most people check the USD/INR rate on the bank’s website and assume that is their cost. It is not. Every INR-USD transaction carries four distinct costs: the bank’s FX spread over the interbank rate, an FX conversion GST computed per Rule 32(2)(b) of the CGST Rules, a flat processing fee, and 18% GST on that processing fee. RealValue FX Engine makes all four transparent in one place — and keeps a permanent log of every deal you’ve booked.
Why RealValue FX Engine?
Traditional bank FX calculators mislead you by:
- Showing only the quoted exchange rate, ignoring service charges
- Hiding the GST amount in fine print
- Giving no way to compare the effective rate across transactions or banks
RealValue FX Engine solves this by:
- Breaking down all four cost components per transaction with per-USD cost and % over interbank
- Computing the FX conversion GST using the official Rule 32(2)(b) formula automatically
- Tracking TCS with correct financial-year accumulation (gross INR thresholds reset each April)
- Showing your effective rate (actual INR cost per USD) for every deal
- Storing every transaction in your browser so you always have a reconcilable log
- Visualising cost composition as a live donut chart with interbank vs. effective rate in the centre
How the Four Costs Are Calculated
For a $1,000 transaction (interbank rate ₹91.85, bank rate ₹93.60, processing fee ₹1,000):
| Component | Calculation | Cost | Per $1 | % vs Interbank |
|---|---|---|---|---|
| Bank FX Spread | 1,000 × (₹93.60 − ₹91.85) | ₹1,750 | ₹1.75 | 1.90% |
| FX Conversion GST | 18% × Rule-32 taxable value | ₹168 | ₹0.17 | 0.18% |
| Processing Fee | Flat | ₹1,000 | ₹1.00 | 1.09% |
| GST on Processing Fee | 18% × ₹1,000 | ₹180 | ₹0.18 | 0.20% |
| Total Extra Cost | ₹3,098 | ₹3.10 | 3.37% |
Rule 32(2)(b) CGST — FX Taxable Value
India’s GST Act prescribes a deemed-value slab for the FX conversion service:
| Transaction Amount (Gross INR) | Rule 32(2) Taxable Value |
|---|---|
| Up to ₹1,00,000 | 1% of amount (minimum ₹45) |
| ₹1,00,001 – ₹10,00,000 | ₹1,000 + 0.5% of amount above ₹1,00,000 |
| Above ₹10,00,000 | ₹5,500 + 0.1% of amount above ₹10,00,000 (max ₹60,000) |
18% GST is then levied on the taxable value above. This is separate from the flat processing fee which also attracts 18% GST.
TCS — Tax Collected at Source
Under Section 206C(1G) of the Income Tax Act, banks collect TCS on LRS remittances. The threshold and rate reset every financial year (April 1 – March 31):
| Cumulative Gross INR in FY | TCS Rate |
|---|---|
| Up to ₹10,00,000 | 0% |
| Above ₹10,00,000 | 20% on the excess |
RealValue FX Engine accumulates gross INR in chronological date order across all your logged Buy USD transactions for the current FY to determine the correct TCS for each deal. TCS is a refundable advance tax — it does not represent a permanent cost.
Transaction Log & History
Every transaction you add is stored in your browser and displayed in a sortable history table with these columns:
| Column | What it shows |
|---|---|
| Date | Trade settlement date |
| Bank | Bank or broker name |
| Trans ID | Your deal / transaction reference |
| USD Bought | Actual USD received for this transaction |
| Gross INR Spent | Total INR debited including TCS |
| Net INR Spent | INR spent excluding refundable TCS |
| Charges | FX spread + processing fee (permanent costs) |
| GST | Total GST (FX conversion + processing fee) |
| TCS | TCS collected (refundable in ITR) |
Built for Real Life
- Designed for Buy USD transactions (LRS remittances, tuition, travel)
- Accepts interbank rate (optional) to compute and display FX spread per component
- Records bank name and transaction ID for bank-statement reconciliation
- Auto-saves every transaction to your browser — no login, no cloud
- Export to JSON for personal records; Import to restore or merge data across devices
- Share button generates a shareable URL encoding the current calculator inputs
- Net USD position summary across all logged transactions
Key Insights
The effective rate is always higher than the quoted rate — the difference is your true cost.
For a $1,000 Buy USD at bank rate ₹93.60 (interbank ₹91.85), processing fee ₹1,000:
- FX conversion GST: ₹168 (18% × Rule-32 value)
- Processing fee: ₹1,000 + GST ₹180
- Bank FX spread: ₹1,750
- Total extra cost: ₹3,098 = ₹3.10 per $1 = 3.37% above interbank
That compounds significantly over large remittances — knowing the breakdown lets you compare banks and timing decisions accurately.
Frequently Asked Questions (FAQs)
Why is my effective rate higher than the quoted USD/INR rate?
Two reasons: the bank’s quoted rate already includes their spread over the interbank rate, and on top of that the bank charges a processing fee and collects FX conversion GST per Rule 32(2). Enter the interbank rate (RBI reference rate) to see the spread component explicitly.
What is the interbank rate and where do I find it?
The interbank (mid-market) rate is the wholesale exchange rate between banks, published by the RBI as the reference rate. You can find it on the RBI website or financial data sites. The difference between the bank’s quoted rate and this rate is the bank’s FX spread — your first cost component.
What is LRS?
The Liberalised Remittance Scheme (LRS) allows resident Indians to remit up to USD 2,50,000 per financial year for permitted purposes (education, travel, investments, gifts, etc.) without prior RBI approval. Each USD Buy transaction you log here can be tracked toward your annual LRS limit.
How is TCS calculated across multiple transactions?
RealValue FX Engine sorts all your logged transactions by date in ascending order and walks the financial year cumulatively. Once the cumulative gross INR exceeds ₹10,00,000 in a FY, TCS at 20% applies on the excess for each subsequent transaction. TCS resets to zero at the start of each new financial year (April 1).
My transaction data is stored where?
All data is stored exclusively in your browser’s localStorage. Nothing is sent to any server. Use the Export button to download a JSON backup before clearing browser data or switching devices.