The calculators on this site do the arithmetic a review is already using: compound growth, a robo-advisor percent, and a bot fee stacked on an exchange fee. They are not a forecast and they do not know your tax rate.
Compound growth, without a story attached
The compound calculator takes a starting balance, a yearly rate, a monthly addition, and a number of years, and it multiplies them. It does not subtract a fee. If you want the fee subtracted, use the robo calculator or read the fee guide, which walks an $80,000 account at 6 percent before a 0.25 percent fee. The compound tool will not warn you that a rate is optimistic. A 10 percent rate typed in is a 10 percent assumption, not a finding of Mintcanopy.
The robo fee calculator
Type the balance, the yearly percent, and the years. The tool multiplies the percent by the balance each year. It is the same operation as the fee guide, with your inputs instead of the $80,000 example. It does not know if your robo-advisor also bills cash. If the contract bills cash, include the cash in the balance you type. The tool does not file your taxes and does not know if the fee is deducted inside a retirement account, where the tax treatment differs.
The bot fee estimator
Type the subscription, the number of fills, the average fill size, and the exchange percent. The tool adds the subscription to the exchange's take. A $24 subscription and forty fills of $500 at 0.10 percent is the worked month in the exchange-fee guide: $24 plus $20. Use the estimator when your fills are a different size. It does not include the spread, and the spread can be larger than either fee on a thin market. Mintcanopy would rather the tool omit the spread than pretend to know it.
What to type
Compound growth wants a start, a rate, a monthly addition, and years. It does not subtract a fee. The robo tool subtracts a percent from the balance each year. Include cash if your contract bills cash. The bot tool adds a subscription to fills times size times the exchange percent. The $24 and forty fills of $500 at 0.10 percent is the guide's month: $44 before the spread. The spread is omitted on purpose.
A rate you type is an assumption, not a finding of Mintcanopy. The tools do not know your taxes.
Three inputs, written down
Compound example: start $80,000, add $500 a month, 6 percent a year, 30 years, no fee. The tool will not subtract 0.25 percent. If you wanted the fee, you opened the wrong box. The fee guide is the walk with the fee on. Use compound when you are only asking what a rate does, and label the rate as an assumption. A 10 percent rate typed into the box is not a finding of Mintcanopy.
Robo example: balance $80,000, fee 0.25 percent, and remember the tool multiplies the percent by the balance you type. It does not add your $500 deposit unless you put the deposit into the balance yourself or use the guide. Include cash if the contract bills cash. Kindling's sweep is the warning: $6,200 of cash at 0.35 percent is still a fee. Bot example: subscription $24, forty fills, $500 average, exchange 0.10 percent. The month is $24 plus $20, which is $44, and the spread is omitted on purpose. Type your own fill size. The demo fill is always large enough to flatter a fixed charge.
What the tools refuse
They do not know your tax bracket, your lot basis, or whether Withdraw is on. Those are the guides. A calculator that asked for a brokerage password would be a different and hostile product, and it would violate the privacy page. The numbers stay in the browser for the arithmetic and are not a portfolio we store.
A wrong input, on purpose
Type 0.25 into the robo tool if the label says percent, and you have asked for a fee of 0.25 percent. Type 0.25 if the label says the decimal and you have asked for 25 percent. The label on this site's tool says percent, and the fee guide uses 0.25 percent in words so the two cannot be confused. Mintcanopy has seen a slide that mixed them. The tool will not save you if you ignore the label. It will multiply what you typed. That is the whole contract of a calculator.
Leave the spread out of the bot tool. If you invent a spread of zero, you have made a thin market look free. The exchange guide says the spread can exceed both fees and refuses to type a zero. The tool matches that refusal by not having a spread field. Add the spread yourself, on paper, after the tool gives you the subscription and the percent. A field we cannot know would be a false precision.
The order of the boxes
Use the compound box only when you are asking what a rate does with no fee. Start $80,000, add $500 a month, 6 percent, 30 years, and label the 6 percent as your assumption. Switch to the robo box when the contract has a percent. The label says percent, so 0.25 means a quarter of one percent, not the decimal 0.25 typed into a field that expected a fraction. Include cash if cash is billed. Then, if the product is a bot, leave both of those boxes and use the bot box: $24, forty fills, $500, 0.10 percent, and read $44 as subscription plus exchange, not as a forecast. Mintcanopy split the tools so a fee cannot hide inside a compound chart. The spread stays on paper because the tool will not invent it.