ReturnKoto?
ReturnKoto? answers one question for people in Bangladesh: if I had put this amount into this mutual fund, what would it be worth today? Type an amount and a period, and it replays that investment over the fund's real published history. It is free, has no ads, and the amount you type stays in your browser.
I built and shipped it in Claude Code. I also wrote the data rules it runs on, which matter more than the code.
On the site today
- Funds tracked
- 38 open-end funds: 20 growth, 11 balanced, 7 income
- AMC-Verified
- 14 of 38, each checked directly with its asset manager
- Shariah-compliant
- 8 of the 38, filterable on the calculator
- Longest history
- 15.5 years of monthly NAVs
- Homepage counter
- "Join 5,590+ people using it", as the site words it
Read from returnkoto.com and its FAQ on 25 Oct 2026. Figures there were comparable through 19 Oct 2026.
The rule: right or withheld
A published figure is either right or not shown. When sources disagree, the code does not pick one. Drift detection stops a bad sync before it reaches a fund page, and anything short of fully confirmed is labelled instead of hidden:
- Added: AMC-Verified: shown only after the asset manager and ReturnKoto? went through the fund's figures together and agreed on what appears.
- Changed: Partial: some dividend records are missing, so the total return may be understated. The page says so.
- Changed: Estimated: a figure is modelled, and labelled as modelled.
- Withheld: two sources disagree on a figure. It stays off the page.
AI made the build fast. The rules are what make the output trustworthy, and they are product decisions, not model behaviour. That split is how I would run AI features on any team.
How a return is computed
Each fund keeps one real NAV per month, the latest published print in that month, from launch to today. The newest point is collected automatically from the fund manager's website and validated before use.
A lump sum buys units once at the starting month's NAV. A monthly SIP buys units every month at that month's NAV.
Cash dividends are reinvested in the payout season at that month's NAV. Stock dividends and unit conversions apply on their effective dates. Every figure is a total return.
Final value is units times the newest NAV. Lump sums annualize with CAGR, SIPs with IRR. Published NAVs are already net of fees.
Where the data comes from
The latest NAV comes from each fund manager's own website. The longer history comes from secondary market data, cross-checked against the managers' figures. Dividends come from the managers' public disclosures. Fees, exit loads, trustees, and minimum investments come from each fund's BSEC prospectus. When one source fails, the pipeline falls back to another.
What you can do on it
Calculate a lump sum or a monthly SIP over any period up to a fund's full history. Compare funds side by side on returns, fees, exit loads, risk, and holdings. Filter Shariah-compliant funds. Weigh any fund against Sanchayapatra, DPS, FDR, gold, and inflation.