# SIP Calculator — project your SIP returns

See what your monthly SIP grows into, with an optional annual step-up. Free, instant, no signup. Interactive calculator at https://spenco.ai/tools/sip-calculator.

## The formula

FV = A × [((1 + i)^n − 1) / i] × (1 + i)

where **A** is the monthly SIP, **i** the monthly return (annual ÷ 12), and **n** the number of instalments.

Example: ₹10,000 a month for 15 years at 12% projects to about ₹50 lakh on ₹18 lakh invested. The projection is only as good as the return assumption — 12% is a common long-run equity assumption, not a promise.

## Year-by-year growth

The calculator shows cumulative invested amount, projected value, and gain at the end of every year. Compounding is back-loaded: the gap between what you put in and what it's worth stays narrow for years, then widens sharply — which is the whole argument for starting early rather than investing more later.

Inputs are shareable: append `?monthly=10000&returnPct=12&years=15&stepUp=0` to the calculator URL to open it pre-filled.

## SIPs are commitments too

A SIP is a promise your salary makes to your future self — and like an EMI, it's a fixed monthly outflow. Spenco parses your SIP debits from bank alerts, tracks them as recurring commitments, and forecasts whether your month can hold them alongside rent and EMIs.

## SIP questions, answered

**What return should I assume for a SIP?** 12% a year is a common long-run assumption for Indian equity funds, but it is an assumption, not a promise. Debt funds run lower (6–8%).

**Is SIP better than a lump sum?** A SIP spreads your buying across market highs and lows (rupee-cost averaging) and matches how salaries arrive — monthly. A lump sum can beat it when markets rise steadily, but a SIP is the plan you can actually stick to.

**What happens if I skip a month?** Most AMCs simply don't debit that instalment (after a few consecutive misses the SIP may be cancelled). But skipped months compound: miss a year of a ₹10,000 SIP and at 12% over 15 years that gap alone costs about ₹5 lakh of final value.

**Are SIP returns guaranteed?** No. A SIP is a way of investing, not a product with a fixed return.

Spenco tracks your SIP debits automatically from your bank alerts. Start free at app.spenco.ai. Also free: Loan EMI calculator at /tools/emi-calculator.