Prepaid Meter Helper (প্রিপেইড মিটার সহায়ক)

A Bengali-first, 100% offline helper for Bangladesh's prepaid electricity meter users.
Recharge breakdown • BERC slabs • Token check • Usage tracker — all in one place.
by tbahsan

বাংলা README (canonical)

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Features

Tab	What you get
Recharge	Where does your ৳1000 go? Meter rent, demand charge, 5% VAT, 0.5% rebate — table + color bar + plain-language explanation + read-aloud
Slabs	BERC residential (LT-A) marginal slabs, step-by-step + average rate
Token	20-digit validator, XXXX-XXXX formatter, meter-entry guide
Usage tracker	Reading log (device-only), month-end forecast, “balance lasts ≈ X days”, CSV export
Appliances	Monthly cost per appliance + “run the AC 2h less” what-if slider
Gas & water	Titas/WASA guides (full calculators on the roadmap)

For everyone: Bengali-numeral input (১০০০), dark mode, print-friendly output, screen-reader support, installable PWA.

Run

Hosted (easiest): https://tbahsan.github.io/utility-token-visualizer/

Locally:

git clone https://github.com/tbahsan/utility-token-visualizer.git
cd utility-token-visualizer
python3 -m http.server 8000
# → http://localhost:8000

JSON won't load over file:// — use any static server.

Install on phone: open the page in Chrome → Add to Home Screen — then it works without internet.

Formula (fully transparent)

base   = recharge − arrears
VAT    = base − base/1.05        (5%, VAT-inclusive treatment)
rebate = 0.5% × base/1.05
energy = base/1.05 − rent − demand + rebate

• Demand Tk 42/kW • Rent: single-phase Tk 40 / three-phase Tk 250
• Slabs are marginal (block-wise) — never flat
• Lifeline Tk 4.63 applies only when total ≤ 50 units
• Tariffs: tariffs/tariffs.json (effective 2026-06-01, verified 2026-09-20)

Mismatch with your receipt? Open an issue with a redacted receipt photo.

File structure

utility-token-visualizer/
├── index.html            # App (Bengali-first)
├── manifest.json, sw.js  # PWA + offline
├── assets/css|js|icons/  # Styles, logic, icons
├── i18n/bn.json, en.json # Languages (bn canonical)
├── tariffs/tariffs.json  # Tariffs (community-updatable)
├── data/appliances.json  # Appliance defaults
└── .github/workflows/    # JSON + i18n + tariff CI

Privacy

• No server, no database, no tracking — everything computes in your browser.
• Readings/settings live only in localStorage; wipe them in one click.
• Zero CDN dependency for core features — fully functional offline.

Contribute

Tariff change? Just update tariffs/tariffs.json + the last_verified date — no coding needed. Details: CONTRIBUTING_BN.md.

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Author

tbahsan
Building open-source, Bengali-first web tools — Rangpur, Bangladesh
github.com/tbahsan • More projects • Bugs / ideas

Support

If this helped you, please ⭐ Star it and share with friends. Every star fuels the next project.

License

MIT © 2026 tbahsan — see LICENSE. Fork it, learn from it, improve it — just keep the original author's credit.

_{Made with care in Rangpur, Bangladesh • রংপুরে যত্নে তৈরি}