DCF Valuation Basics For Interviews

Reviewed by Fallon Han· Updated 2026-06-01 06:05:33.032

This conversation was generated using Cook'd AI's career assistant and reviewed by Fallon Han from our editorial team for accuracy.

I am a final-year economics student in India and I am preparing for a bulge-bracket investment banking internship in Singapore, with visa sponsorship needed. Can you give me a simple end-to-end explanation of how a DCF is built and how the pieces fit together? I want the big picture before the details.

Absolutely. Think of a DCF as a way to estimate what a business is worth today based on the cash it can generate in the future. The full logic has four main steps: 1. Forecast free cash flows You start by estimating the companys future cash flows for a few years, usually 5 or 10. This is the operating part of the model, where revenue, margins, taxes, and reinvestment assumptions drive the numbers. 2. Pick a discount rate Because future cash is worth less than cash today, you discount those projected cash flows back to the present using the companys weighted average cost of capital, or WACC. 3. Estimate terminal value Since a business usually keeps operating beyond the explicit forecast period, you add a terminal value to capture all cash flows after the forecast window. This is often the largest part of the valuation, so assumptions here matter a lot. 4. Sum everything to get enterprise value You discount the forecast cash flows and terminal value back to today, add them up, then move from enterprise value to equity value by adjusting for debt, cash, and other non-operating items. The pieces fit together like this: operating assumptions drive free cash flow, the discount rate converts those future cash flows into present value, and the terminal value captures the long tail of the business. For interviews, the key is to explain the logic clearly, not just recite formulas. If you want, we can go one layer deeper next into how WACC is built and why it is used.

That helps. Can you walk me through WACC in a very practical way? I understand it is the discount rate, but how do equity and debt fit in, and why do bankers use it instead of just one required return?

Great question. WACC is basically the blended return that all capital providers require from the business. It combines: - Cost of equity, which is the return equity investors expect for taking ownership risk - Cost of debt, which is the effective interest cost on borrowings, adjusted for the tax shield because interest is tax deductible The standard idea is: WACC = weight of equity times cost of equity plus weight of debt times after tax cost of debt Why bankers use it: - DCF usually values the entire operating business, not just equity - The cash flows being discounted are typically unlevered free cash flows, meaning cash flows available to both debt and equity holders - So the discount rate should reflect the return required by both groups together In practice, the cost of equity is usually estimated using CAPM, which means risk free rate plus beta times equity risk premium. Debt is easier, since it is based on observable borrowing rates, then adjusted for tax. A common interview point is that WACC only makes sense if the companys target capital structure is reasonably stable. If leverage changes a lot, the discount rate should be treated more carefully. If you want, I can next connect this to free cash flow and explain why DCF uses unlevered rather than levered cash flow.

Yes, please connect free cash flow and the discount rate. I keep mixing up levered and unlevered cash flow, and I want to understand why DCF usually starts with unlevered free cash flow.

That distinction is very important. Unlevered free cash flow is the cash the business generates before debt financing. It belongs to all capital providers, so it is the right cash flow to pair with WACC. A simple way to think about it is: EBIT minus taxes plus non-cash charges like depreciation minus capex minus changes in working capital equals unlevered free cash flow Why this works: - EBIT is before interest, so it is not affected by how the company is financed - That means the valuation reflects the business itself, not the current debt structure - Then, once you have enterprise value, you can subtract debt and add cash to reach equity value Levered free cash flow is after interest payments and reflects what is left for equity holders only. That is useful in some contexts, but not for a standard enterprise DCF. So the logic is: - Unlevered cash flow goes with WACC - Levered cash flow goes with cost of equity For interviews, I would say: DCF uses unlevered free cash flow because the model values the operating assets independent of capital structure. Next, we can connect this to terminal value, since that is usually where candidates get most of the conceptual questions.

Yes, terminal value confuses me the most. How do I think about it intuitively, and how does it connect back to the forecast period and the discount rate?

Think of terminal value as the value of everything the company will earn after your explicit forecast period ends. Because you cannot forecast every single year forever, you usually model 5 to 10 years in detail and then assume the business enters a more stable phase. There are two common approaches: 1. Perpetuity growth method You assume free cash flow grows at a steady long run rate forever. This is simple and widely used. 2. Exit multiple method You apply a valuation multiple, such as EV to EBITDA, to the final forecast year. This is often used as a market cross check. How it connects to the forecast period: - The forecast period captures the companys near term transformation, such as margin expansion, scale benefits, or capex cycles - Terminal value captures the mature steady state beyond that period How it connects to the discount rate: - The terminal value is also discounted back to today, just like the yearly cash flows - Because it is often a large number, small changes in WACC can materially change the valuation A good interview answer is: terminal value is the present value of all cash flows beyond the explicit forecast horizon, and it usually represents the biggest share of DCF value, so the assumption behind it must be conservative. If you want, I can now link terminal value and discount rate to sensitivity tables, which is the part that really matters in banking presentations.

Yes, please. How should I read a sensitivity table in a DCF, and what does it tell me about the relationship between WACC, terminal growth, and valuation? I want to be able to discuss it in an internship interview.

A sensitivity table is basically a quick way to show how fragile or robust the valuation is when key assumptions change. Most DCF sensitivity tables vary two inputs: - WACC on one axis - Terminal growth rate or exit multiple on the other axis What it tells you: - Higher WACC means lower valuation, because future cash flows are discounted more heavily - Higher terminal growth means higher valuation, because the business is assumed to grow faster after the forecast period How to read it in practice: - The base case is usually in the middle - If you move up in WACC, value should drop - If you move right in terminal growth, value should rise - The table shows how much the valuation changes if your assumptions shift a little Why bankers care about it: - It shows whether the deal or investment is highly dependent on optimistic assumptions - It helps discuss valuation range, not just one point estimate - In interviews, it demonstrates that you understand DCF is assumption driven, not a precise truth A strong way to explain it is: sensitivity analysis helps test how much the valuation depends on the discount rate and terminal assumptions, which are usually the two biggest drivers of value. If you are preparing for Singapore investment banking interviews, this is a good moment to sound practical: mention that you would sanity check the implied valuation against trading comps and transaction comps, not rely on DCF alone.