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I am Tharindu De Silva, a dedicated banking professional with a strong passion for treasury operations, capital markets, and financial analytics. With hands-on experience in treasury management and a keen interest in developing practical tools, I built this suite of calculators to assist professionals in making informed decisions. I believe in continuous learning and sharing knowledge to empower the financial community.
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Professional calculators for Treasury, Banking, Capital Markets & Personal Finance — all in one trusted platform.
Price, yield, accrued interest and capital gain/loss calculations for Sri Lankan Treasury Bills (A/364).
Bond pricing, YTM, accrued interest, amortization, gain/loss and duration/convexity analytics.
Equity valuation, profitability, return and cost of equity measures.
Spot, forward, swap points and swap value calculations for FX (USD/LKR priority).
Repo interest, maturity amount and collateral exposure / minimum face value required.
Mortgage, EMI, auto loan, compound interest, retirement, ROI and NPV/IRR calculators.
Allocate cash across T-Bills, T-Bonds, Equity, and FDs. Track unallocated funds and manage multi-deal portfolios.
Calculate individual income tax payable based on Sri Lanka Inland Revenue Department rules (effective 1 April 2025).
Individual tax calculation based on Inland Revenue Department rules — effective 1 April 2025
| Taxable Income (LKR) | Tax Rate |
|---|---|
| First 1,000,000 | 6% |
| Next 500,000 | 18% |
| Next 500,000 | 24% |
| Next 500,000 | 30% |
| Balance | 36% |
Source: Inland Revenue (Amendment) Act, No. 02 of 2025 — effective 1 April 2025. Personal relief increased from LKR 1,200,000 to LKR 1,800,000.
Assessable Income is the total income received or derived during the Year of Assessment from the following sources, before deducting Personal Relief or Qualifying Payments:
Do not include income that is specifically exempt or excluded under the Inland Revenue Act (for example, certain terminal benefits, approved pension income, or exempt investment gains as defined in the Act). Only enter the taxable portion of your total income here.
The IRD website explicitly states that donations made in money to an Approved Charity are deductible from Assessable Income as a Qualifying Payment.
The deductible amount is limited to the lowest of the following three values:
The Inland Revenue Act lists other qualifying payments (e.g., contributions for Samurdhi shop establishment, film industry expenditure), but their current-year applicability and caps are not confirmed in the IRD documents available at the time of this update. Only enter amounts you can substantiate as valid Qualifying Payments for the relevant Year of Assessment. If unsure, enter 0 to avoid an inaccurate tax computation.
Treasury Bill pricing and yield calculations (Sri Lanka: A/364)
Government bond pricing, yield, accrued interest and gain/loss (Sri Lanka: A/A)
Equity valuation, dividend, profitability and return calculations
Foreign exchange spot, forward, swap points and swap value calculations (Sri Lanka priority: USD/LKR)
Repo interest and collateral exposure calculations (Sri Lanka: CBSL standards)
Everyday money tools — loans, savings, retirement and returns
| Taxable Income (LKR) | Tax Rate |
|---|---|
| First 1,000,000 | 6% |
| Next 500,000 | 18% |
| Next 500,000 | 24% |
| Next 500,000 | 30% |
| Balance | 36% |
Source: Inland Revenue (Amendment) Act, No. 02 of 2025 — effective 1 April 2025. Personal relief increased from LKR 1,200,000 to LKR 1,800,000.
Assessable Income is the total income received or derived during the Year of Assessment from the following sources, before deducting Personal Relief or Qualifying Payments:
Do not include income that is specifically exempt or excluded under the Inland Revenue Act (for example, certain terminal benefits, approved pension income, or exempt investment gains as defined in the Act). Only enter the taxable portion of your total income here.
The IRD website explicitly states that donations made in money to an Approved Charity are deductible from Assessable Income as a Qualifying Payment.
The deductible amount is limited to the lowest of the following three values:
The Inland Revenue Act lists other qualifying payments (e.g., contributions for Samurdhi shop establishment, film industry expenditure), but their current-year applicability and caps are not confirmed in the IRD documents available at the time of this update. Only enter amounts you can substantiate as valid Qualifying Payments for the relevant Year of Assessment. If unsure, enter 0 to avoid an inaccurate tax computation.
Allocate your cash across different investment instruments