Introduction
For many types of institutions, financial metrics are used to compute and view the outcome of investments or cash flow. More people use some of them than others. The decision is based on the information the owner wants to obtain.
In the world of business and finance, NPV and ROI are two words that are both widely used and helpful. One should be able to distinguish between numerous terminologies employed in the process of calculating the results of the business if one is establishing a new company or firm.
The primary distinction between NPV and ROI is that each metric is utilised to compute a different outcome. While ROI is used to calculate the company's increased cash flow, NPV shows the user the present value of the investment.
NPV vs ROI
The net present value of a company's current cash flow is provided by NVP. Either a positive amount or a negative amount could be the outcome. A low return is indicated by a negative or unfavourable total. Investments are discounted based on today's prices during the calculation. ROI is a metric used in finance to assess the profitability of a cash flow investment. Following the computation, it is possible to distinguish between lucrative and unsuccessful investments. The measure can be calculated in a few different ways, depending on the needs of the business.
The difference between the present (and/or discounted) value of future cash flows and the present value of the investment less any potential future cash flow accumulation is known as the net present value, or NPV. In essence, it shows the return on a longterm investment (expressed in USD).
An equation that assesses an investment's effectiveness is known as the Return on Investment (or ROI). In essence, it is the ratio of the gain on an investment to the cost of the investment, divided by the cost of the investment:
(Return on Investment  Investment Cost) / Investment Cost
Regarding the NPV, one must keep in mind that this number is not employed to calculate investment amounts. It is merely a figure that the investor uses to gauge how much cash flow he is receiving as a result of his investment. It is also used to estimate (or forecast) the amount of future cash flow; because it considers the discount rate, it does not consider profits and losses in the conventional sense.
When attempting to estimate future cash flow based on the cash flow that an investment is currently gathering, one must take into account that the ROI has no real merit. It is merely a means to track the cumulative profit (or return) on an investment. It is one of the most widely used metrics to gauge the performance of an investment because of its simplicity and adaptability, but it is also a fantastic predictor of where your investment stands. An investment should not be considered at all if it has a negative return on investment (ROI) or if there are more profitable options that use an entirely different ROI.
However, both values do have drawbacks. Although the initial investment required is not precisely calculated, the NPV value does take into account the discount rate of the dollar value at present and in the future. It may appear that two ventures with an NPV of $100 are both profitable, but if one demands a $10,000 commitment while the other requires $1,000,000, it is clear that the former is a considerably more promising investment. On the other side, the issue arises when entering the investment information because the ROI is such a straightforward equation and is easily altered.
Difference Between NPV And ROI in Tabular Form
Parameters of comparison

NPV

ROI

Extension

Value Net Present

Income From Investment

Definition

A statistic called NPV looks at a company's cash inflows and outflows.

The ratio of net income to investment is revealed by the financial metric known as ROI.

Formula

NPV= cash flow / (1 + i)t – initial investment

ROI= (Total benefits – total costs) / total costs

Another name

Net present worth (NPW)

Return on invested capital

Advantage

Help with business decision planning, including advice on the time value of money, etc.

Describes the status of investments and aids in comparisons between various investments, etc.

Disadvantage

Due to omitting additional costs, such as hidden fees, the sum may not be entirely correct.

The outcome is that a return cannot be made in a shorter period of time, etc.

What is NPV?
Net Present Value is NPV. The gap between current investments in the business's cash inflows and outflows is calculated using this financial metric. It essentially conveys the profitability of a project or investment. Seeing which investments are successful and which are not aids management or the owners. Three circumstances can lead to the outcome. Where the NPV is positive, first. NPVs that are negative and zero are the following. The first two are typically the outcomes. Zero net present value denotes parity between the asset and its value.
If the NPV is positive, the investments will be profitable for the government. It is carried out after a set amount of time and is a fairly typical part of the capital budgeting process. The tool is simpler than others that have been used to calculate profitability.
NPV compares similar investment options by taking time value of money into account. Any project or investment with a negative net present value (NPV) should be avoided since the NPV depends on a discount rate that may be calculated from the cost of the capital needed to invest. 1 The fact that NPV analysis makes potentially unreliable assumptions about future events is a significant disadvantage.
The NPV method uses the premise that a dollar's value will change over time to determine the profitability of a particular investment. Due to inflation, money loses value over time. A dollar today, however, can be invested and generate a return, potentially increasing its value over a dollar acquired at the same time in the future.
NPV aims to calculate the present value of future cash flows from an investment that are greater than the investment's initial cost. The NPV formula's discount rate component reduces future cash flows to their presentday value. The investment is worthwhile if the result of deducting the initial investment cost from the total of the cash flows in the present is positive.
An investor might, for instance, get $100 today or in a year. The majority of investors would not be eager to delay getting $100 today. What if an investor had the option of choosing between receiving $100 today or $105 in a year? If another investment might provide a rate higher than 5% over the same time period, the 5percent rate of return (RoR) after a year would be beneficial to the investor. An investor would opt to accept $100 today rather than the $105 in a year, with the 5 percent rate of return, if they knew they could earn 8 percent from a generally safe investment during the next year. In this instance, the discount rate would be 8%.
A financial statistic called net present value (NPV) aims to quantify the total value of a potential investment opportunity. The goal of NPV is to forecast all potential future cash inflows and outflows related to an investment, discount each one to the present, and then tally them all up. The investment's net present value (NPV) is the sum of all the positive and negative cash flows. A positive NPV indicates that, after taking into account the time value of money, making the investment will result in a profit.
What is ROI?
ROI stands for Return on Investment. It is a metric used to assess the performance of investments in any corporation. It is easy to calculate than other metrics. Hence, it is the most often used mnetric. A higher value of ROI is good for the business. But there are several drawbacks to this method also. For example, the result of any longterm investment cannot be dteremined effectively. There are several methods to calculate ROI. One of them is as follows:
Current Value of Investment  Cost of Investment) / Cost of Investment
Because of its adaptability and simplicity, ROI is a wellliked metric. In essence, ROI serves as a basic indicator of an investment's profitability. This could be the return on investment (ROI) from a stock purchase, the ROI a business anticipates from expanding a manufacturing plant, or the ROI produced in a real estate deal.
For its wide range of applications, the computation itself is not overly difficult to understand. If an investment has a net positive return on investment, it probably makes sense. However, these indications can aid investors in excluding or picking the best possibilities if other opportunities with greater ROIs are present. Investors should also steer clear of negative ROIs since they indicate a net loss.
Consider Jo buying $1,000 worth of shares of Slice Pizza Corp. in 2017 and selling them for $1,200 a year later. Divide the net profits ($1,200  $1,000 = $200) by the investment cost ($1,000) to get the return on investment (ROI), which is $200/$1,000 or 20%.
With this data, it would be possible to evaluate the investment in Slice Pizza in relation to other projects. Let's say Jo also put $2,000 into BigSale Stores Inc. in 2014 and then sold the shares for $2,800 in total in 2017. Jo's investments in BigSale would have a return on investment (ROI) of $800/$2,000, or 40% The rate of return (RoR), which considers the duration of a project, can be used in conjunction with ROI. Another option is to utilise net present value (NPV), which takes inflation into account when adjusting for changes in the worth of money over time. Real rate of return is a term that refers to the use of NPV when determining RoR.
What Is ROI in Simple Terms?
Return on investment (ROI) essentially shows you how much money you made (or lost) on a project or investment after deducting its cost.
Main Difference Between NPV and ROI in Points
 While ROI determines the return on invested capital, NPV is the amount of the present value of any investment made in a financial organisation.
 An absolute number is the outcome of NPV. ROI, on the other hand, is a percentage. Different estimations are generated using both metrics.
 To determine if an asset is feasible or not, the present value of the asset is calculated using NPV. On the other side, ROI is estimated so that one can assess and contrast various business investments.
 NPV might alter the outcome of the end amount in error because it is based on future assumptions. Since ROI is not based on predictions for the future, there are less inaccuracies in its calculation.
 NVP is calculated while taking risk into consideration. On the other hand, ROI does not include any risk. After a predetermined amount of time, it becomes usable if the user chooses to do so; otherwise, it is not.
 NVP is adjusted for time whereas ROI is not.
Conclusion
Using one of these or any other kind of measure relies on the user's requirements and preferred method. These days, a wide variety of firms and software providers calculate these metrics, relieving the investor of that duty.
Before beginning to calculate either statistic, the user should be aware of both of its benefits and drawbacks. They are widely used and very helpful in reviewing investments and the profit generated by them. , which are crucial for choosing what to do with the business.
References
 https://books.google.co.in/books?id=UQT0AMDZ3w4C&pg=PA98&dq=npv+and+roi&hl=en&sa=X&ved=2ahUKEwiE6ual8fxAhWzoekKHTo0CTsQ6AEwBHoECAwQAw#v=onepage&q=npv%20and%20roi&f=false
 https://books.google.co.in/books?hl=en&lr=&id=m7CWxNx53h8C&oi=fnd&pg=PR6&dq=info:u9f3a4_JRtEJ:scholar.google.com/&ots=8c4ctK0VzT&sig=Q66v40LxdbYSvKJCmEXKnQWnptA&redir_esc=y#v=onepage&q&f=false