Free · No signup · Runs in your browser

The back office, without the busywork.

A small, opinionated collection of finance and bookkeeping tools for founders, freelancers, and operators. Built to be fast, focused, and respectful of your time.

లెక్క · Lekkal · Telugu for ledger, accounts, bookkeeping

All tools

Live

Invoice generator

Create polished, downloadable PDF invoices in seconds. Multi-currency, tax, discounts, line items, your logo — no watermark, no signup.

Live

Marketing ROI calculator

CAC, LTV, ROAS, payback period, and a unit-economics health verdict. Plug in spend, traffic, and customer numbers — get a clear read in seconds.

Live

GST calculator (India)

Add or extract GST with the standard slabs (0/5/12/18/28%). CGST + SGST split for intra-state, IGST for inter-state. Copy-paste-ready summary.

Live

Income tax (India)

Compare new and old tax regimes for FY 2025-26. Includes 87A rebate, marginal relief, surcharge, 4% cess, and all major deductions — 80C, 80D, HRA, home loan, NPS.

Live

SIP calculator (India)

Project your mutual fund corpus across regular, step-up, and lump sum modes. Year-by-year growth chart with optional inflation adjustment.

New

Salary breakup (India)

Convert your CTC to monthly in-hand. Full structure: Basic, HRA, EPF, gratuity, professional tax, income tax. New vs old regime side-by-side.

Live

Loan & EMI calculator

Monthly payment, total interest, and a full amortization schedule for any loan — mortgage, car, personal, education. Six currencies with regional default rates.

Live

Burn rate & runway

Cash, monthly burn, runway in months, and a cash-trajectory chart. Model revenue growth to see when you'd hit profitability.

Live

Cap table & dilution

Model founder ownership across pre-seed, seed, Series A and beyond. ESOP refresh, pre-money math, per-round chart. The hidden dilution math, made visible.

Live

MRR / ARR / NRR

SaaS metrics from one month of data — net new MRR, NRR, GRR, customer + revenue churn, ARPU. Includes a 12-month compound projection.

New

Hourly rate (freelancers)

Target salary + overhead + profit margin + billable utilization → required hourly, daily, and project rates. The number most freelancers chronically underestimate.

New

Compound interest & FIRE

Project savings or retirement corpus with monthly contributions and inflation adjustment. Includes a FIRE target check.

New

Break-even calculator

Fixed costs + price + variable cost per unit → break-even in units and revenue, contribution margin, and margin of safety. With a revenue-vs-cost chart.

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Profit margin & markup

Cost + price → margin %, markup %, and gross profit. Or set a target margin to find your price. Settles the margin-vs-markup confusion for good.

New

NPV & IRR calculator

Discounted cash flow, made readable. Initial investment + discount rate + cash flows → NPV, IRR, payback period, and profitability index, with a cumulative cash-flow chart.

New

Expense splitter

Settle group expenses from a trip, dinner, or shared rent. Pick who's in on each cost and get the fewest payments needed to settle up. Multi-currency.

New

LLM API cost calculator

Estimate AI spend per call, day, and month from tokens and volume — then compare GPT, Claude, Gemini and more side by side to find the cheapest model for the job.

New

AI feature unit economics

Does your AI feature make money per user? Work out AI cost per user, gross margin, and the usage level where the feature stops paying for itself.

New

AI automation ROI

Manual cost vs AI cost for a repetitive task → monthly savings, payback period on setup, and the hours you free up. Build the business case in seconds.

New

Self-host vs API

The fixed cost of running your own GPUs vs pay-as-you-go API pricing — see the request volume where self-hosting an LLM finally becomes cheaper.

New

LLM token counter

Paste any text to estimate its tokens, then price it as a prompt across models. Runs in your browser — nothing you paste is uploaded.

Frequently asked questions

Are these tools really free?

Yes — every tool on Lekkal is free to use, with no signup, no watermark on outputs, and no usage limits. We may add a paid tier in the future with extra features (auto-save, team workspaces, API access), but the core tools will remain free.

Does Lekkal store my data?

No. All Lekkal tools run entirely in your browser. Your invoice data, calculator inputs, and other information never leave your device. Saved drafts are stored only in your browser's local storage, which you control.

What does "Lekkal" mean?

Lekkal (లెక్క) is a Telugu word meaning ledger, accounts, or bookkeeping. We chose it because it captures what these tools are for — keeping the books, running the numbers, and making the back office painless.

Can I use these tools commercially?

Absolutely. The tools are designed for founders, freelancers, agencies, and small businesses. Invoices generated by Lekkal are commercially valid and contain no Lekkal branding or watermarks — they're yours to send to clients as-is.

Will you add more tools?

Yes — we ship new tools regularly. Recent additions include the NPV & IRR calculator and the expense splitter, alongside GST, EMI, burn rate / runway, and ROI calculators and the invoice generator. If there's a specific tool you'd find useful, drop us a note on GitHub.

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