If you are looking for a one stop shop for all of your calculation and conversion related issues then you should know that there are multiple such websites out there that can help you in this case. Since there are so many different fields of life in which you need to use calculations and conversions, it is impossible to keep a track of things or do it yourself manually, in such situations finding a good conversion and calculator websites are your best bet as they help you in navigating in the world of measurements and conversions and make your job much easier.
However, one thing that you need to keep in mind is that although some websites have all the calculators available to you for your usage, there will be some of them that will charge you a minimal fee for the calculation which is completely understandable; but one website which is known by the name of gigacalculator.com and is quite popular because of all the free calculation and conversion services that they offer to the people, catering to a variety of fields from finances, fitness to academic fields.
A lot of these websites also tend to have their calculator and conversion widgets as well that you can use to embed in personal or professional blogs accordingly. The great thing about these websites is that they are catering to a diverse class and groups of people based on their requirement. However, as we mentioned before some websites will charge you for their services while others will do it all for free for you along with some other services like giving free widget access as well that can be conveniently placed in your blogs as well. Some bloggers hire their services on contract as well.