BeginnerBonds

Bond Pricing & Yield

A bond's price is the present value of all its future cash flows. Discount each coupon and the principal back to today — add them up — that's the price.

Bond Parameters

5%
0%12%
5%
0.5%12%
5 yrs
1 yrs30 yrs
Bond Price
$1000.00
Par Bond
Coupon PV
$218.80
21.9% of price
Principal PV
$781.20
78.1% of price
Current Yield
5.00%
Total Cash Flow
$1250
nominal (undiscounted)

Cash Flow Waterfall — Nominal vs Present Value

Each bar shows the nominal cash flow (tall, faded) versus its present value (short, colored). The dashed red line is the time value of money — future money is worth less today.

$0$295$589$884$1.2k$240.5y$24Y1$231.5y$23Y2$222.5y$22Y3$213.5y$21Y4$204.5y$801Y5Time to Cash Flow
Nominal (future value)
Coupon PV (discounted)
Principal PV (discounted)
Time value of money

Price-Yield Curve

par$1000.00$705$821$936$1052$1167$12830.5%2.4%4.3%6.3%8.2%10.1%12.0%Yield to Maturity (%)
5%
0.5%12%

Par, Premium & Discount

PREMIUM BOND

Coupon > Yield → Price > Face Value

Investors pay more because the coupon payments are higher than what the market requires.

PAR BOND

Coupon = Yield → Price = Face Value

The coupon exactly compensates for the required yield. Price equals face value.

DISCOUNT BOND

Coupon < Yield → Price < Face Value

The coupon is below market rates, so investors pay less to achieve the required yield.

The Bond Pricing Formula

Bond price (what you pay today)
Coupon payment per period
Face value (par, typically $1,000)
Yield per period (YTM ÷ frequency)
Total number of periods
Each period (1, 2, 3, ... n)

Step-by-step: How it works

1

List all future cash flows

A 5-year bond with 5% coupon, semi-annual, $1,000 face → you receive $25 every 6 months + $1,000 at the end = 10 coupon payments + principal.

2

Discount each cash flow to today

Each payment is divided by — money further in the future is discounted more heavily. This is the time value of money: $25 received in 5 years is worth less than $25 today.

3

Sum them up = Bond Price

The sum of all discounted cash flows — that's in the formula. The bond price is literally the total present value.

Key Relationships

Price and Yield move inversely

When yields rise, you discount cash flows at a higher rate → each is worth less → price falls. When yields fall, the opposite: each cash flow is worth more → price rises. This is the most fundamental relationship in bond markets.

Longer maturity = More sensitivity

A 30-year bond's price moves much more for the same yield change than a 2-year bond. This is because more cash flows are being discounted over longer periods. This concept is formalized as duration.

The curve is convex, not linear

Notice the price-yield curve bends — it's not a straight line. A 1% yield drop gives a bigger price gain than the price loss from a 1% yield rise. This asymmetry is called convexity, and it's always positive for vanilla bonds.