Coastline vs Vanguard
Vanguard’s Retirement Nest Egg Calculator is a clean, free Monte Carlo tool that answers one focused question: will a given balance last a given number of years at a given spending level? Coastline covers far more of the plan — building the nest egg, the taxes on it, Social Security timing, and withdrawal strategy — with the math shown.
Coastline vs Vanguard, feature by feature
| Coastline | Vanguard | |
|---|---|---|
| Free, no signup | Yes | Yes |
| Monte Carlo "will it last" simulation | Yes | Yes |
| Accumulation (working years) modeling | Yes | No |
| Federal + state income tax math | Yes | No |
| Social Security / other income | Yes | No |
| Roth conversion / withdrawal-order strategy | Yes | No |
| Year-by-year detail | Yes | No |
| Speed for a quick gut-check | Fast | Fastest |
When to use Vanguard
Vanguard’s calculator is perfect for a 30-second gut-check: plug in a balance, a spending figure, an allocation, and a number of years, and see the probability it lasts. Nothing beats it for simplicity.
When to use Coastline
Choose Coastline when a single probability isn’t enough — when you want the taxes, Social Security, account-mix strategy, and the year-by-year picture of how the money is built and spent, with every number explained.
Both tools are free. This comparison is written by Coastline, so weigh it accordingly — try both and use whichever answers your question. Vanguard is a well-regarded tool; the differences below are about focus, not quality.
Common questions
What does the Vanguard Nest Egg Calculator do?
It runs a quick Monte Carlo on whether a starting balance survives a set number of years at a chosen withdrawal amount and stock/bond mix. It doesn’t model taxes, Social Security, or accumulation — Coastline does.
Is Coastline more accurate than Vanguard’s calculator?
They answer different questions. Vanguard gives a fast survival probability; Coastline models taxes, income sources, and strategy in detail, which matters for real spendable income. For a quick check, Vanguard’s is great; for a full plan, Coastline goes deeper.
Are both free?
Yes. Both are free; Coastline additionally requires no signup.