This is over my head

Howdy @peterkilaba

This one is a little tricky but I think I understand.

You’ll probably need to use an input with a custom formula to perform the calculation. Then you can update the record with the value of the input.

This can be a hidden/transparent input (by placing the input behind a rectangle and/or setting the colors to transparent).

It would help to understand how you have the parameters/variables loading on the screen. Can you provide a little more info?

I would recommend using Loom to record your screen, going over the data and how you’d like to achieve the calculation.

Since there are bunch of brackets and exponents, how so I write it down on custom formula or how I break it down so the solution is correct. Thanks

P = Principal amount
r = Annual nominal interest rate as a decimal
n = number of compounding periods per unit of time
t = time in decimal years; e.g., 6 months is calculated as 0.5 years. Divide your partial year number of months by 12 to get the decimal years.

Where do each of these parameters reside? Do the users manually enter these numbers into inputs? Are these parameters part of a collection?

Again, you need to provide more information. Without understanding how you get your numbers, it’s impossible to explain how to set up a solution.

The user just enter the downpayment amount and chooses loan term and interest rate from different banks and I want them see their monthly payment from different banks

Hm. Let me think about it.

Thanks @Flawless. Really appreciated…

Yup, this one’s tricky. I can’t get the calculation to work right after a few attempts either. Lol. I messaged someone that I think can help but have not yet heard a reply. I’ll get back to you when I hear something.

Just giving a try :slightly_smiling_face:

Am I correct?


Two texts are two formulas and different results based on the formula!

You’re running into the same kind of issue that I was running into.

Based on the numbers you’ve provided in your example @dilon_perera the monthly payment for a loan amount of $67,890 over 4 years with a 5% interest rate should be $1,563.46.

The formula isn’t working right and does not provide the correct answer.

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Have you guys tried to break up different pieces and do the math that way?

That was going to be my next trial. Had to close it to refresh the brain for a bit.

Ok guys @dilon_perera @Flawless @Yongki
So sorry I gave you wrong formula, the one I gave gives total payment but what I needed is for monthly payment I found one with examples below.
I’ve been trying to do this one but I can’t figure how to calculate this sign ^ ,what the heck is this?

What is my loan payment formula?

If you have an amortized loan, calculating your loan payment can get a little hairy and potentially bring back not-so-fond memories of high school math, but stick with us and we’ll help you with the numbers.

Here’s an example: let’s say you get an auto loan for $10,000 at a 7.5% annual interest rate for 5 years after making a $1,000 down payment. To solve the equation, you’ll need to find the numbers for these values:

  • A = Payment amount per period
  • P = Initial principal or loan amount (in this example, $10,000)
  • r = Interest rate per period (in our example, that’s 7.5% divided by 12 months)
  • n = Total number of payments or periods

The formula for calculating your monthly payment is:

A = P (r (1+r)^n) / ( (1+r)^n -1 )

When you plug in your numbers, it would shake out as this:

  • P = $10,000
  • r = 7.5% per year / 12 months = 0.625% per period (0.00625 on your calculator)
  • n = 5 years x 12 months = 60 total periods

So, when we follow through on the arithmetic you find your monthly payment:

10,000 (.00625 x (1.00625^60) / ((1.00625^60) - 1)

10,000 (.00625 x 1.45329) / (1.45329 - 1)

10,000 (.00908306 / .45329)

10,000 (.02003808) = $200.38

In this case, your monthly payment for your car’s loan term would be $200.38.

Hello @peterkilaba,

We have a powerful Math API that let you make advanced calculations like the one that you are trying to do.
Here you can find the link of the details of the API (under Math API category, you will need to select the Calc API)

Here is the post of the announcement of the Math API:

We have also prepared a quick video showing you how the Calc API can calculate your expression:

If you would like to get your free account please visit and you can sign up directly on our homepage!

Do not hesitate to contact us for any detail! We will be happy to help you!


Oh! I Forgot Abracadalo :man_facepalming: That’s cool!

But just tried again! :slightly_smiling_face:

Without a button : without a button.mp4 - Google Drive

With a button : with a button.mp4 - Google Drive

I checked all the calculations with this calculator and they were correct!

Let me know!

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Hey @dilon_perera looks like this is exactly what I’ve been looking for but I have no idea how to make it work on my app, would kindly give me step by step on how to make it work on my app? I really appreciate it

Yeah sure! I didn’t made a video first because need to confirm if I’m correct! Can you confirm?Or someone? And for everyone’s information in here to do this I used JS! :raised_hands:

Yes this I think will be beneficial for lots of people, really appreciated @dilon_perera

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Hi @peterkilaba,

Here’s the video! : Loom | Free Screen & Video Recording Software

Edit. I made this simpler and you don’t need a input to divide the rate by 100. I have added that directly to the code! Updated the video too!

Here’s the script :

var Rate = "5" / 100;
var Term = "48";
var Price = "67890";
var value = Price * (Rate/12) * (Math.pow((1 + (Rate/12)), Term))/ ((Math.pow((1 + (Rate/12)), Term)) - 1);
var value = Math.round(100*value)/100;
return value;

In here change the rate inside double quotes with the drop down’s rate and for the term, term drop-down value and for the price add the input that user type the amount.

Instructions to download components from Pragmaflow website : PragmaFlow's Adalo Marketplace Reopened - YouTube

Pragmaflow website : PragmaFlow Adalo Toolkit

The component you need :


And also you can hide the inputs and the JS component!

Thank you

Thank you so much for taking the time to so this. I really appreciated, let me try to do this.Thanks.

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