Paragon is not linear. 1000 paragon + 1000 paragon is not 2000 paragon because you need to add the XP required for 1000 paragon to itself and then calculate what paragon that would be.

This is useful to for example figure out what paragon you will be in non-season when the season ends and your season paragon gets rolled into it.

Calculates actual XP/hr over a session based on starting and ending paragon.

Times are for a 24hr clock (i.e. 22:00 is 10:00pm, aka "military time"). If start time is after end time then the end time is assumed to be the next day. 22:00 - 02:00 is 4 hours.

Pools of Reflection grant 25% bonus XP from monster kills and Greater Rift Turn-in until they run out.

You can have up to 10 pools stored on your character before it caps out, which is equivalent to the amount of XP needed to gain a full level.

This means as you level up, you can "hold" more XP as bonus pool XP.

However, there is a bug with the XP gained from Greater Rift turn-ins. Instead of receiving a single 25% bonus, the XP gain is compounded again multiplicatively. This means that the bonus XP gained is 56.25% (1.25 x 1.25) rather than 25%.

Additionally, the amount of XP consumed by the Greater Rift turn-in is only from the second compounded 25%, which results in only ~55.6% of the bonus XP gained being consumed by the turn-in.

Blizzard has been made aware of this bug many times and they have not fixed it, so at this point it's assumed to be "working as intended."

The calculator below takes this bug into account.

Note that in Season 28 (Feb 24th, 2023), pools of reflection are no longer consumed, which means you can benefit from their bonus XP indefinitely. However, there's a catch: it appears that this mechanic doesn't provide the full benefit of a Greater Rift close at lower paragon levels. After gaining at least one pool, a player is set to the equivalent of 10 pools at all times, but this may not be enough to fully benefit from the bonus XP of a GR close at low paragon. Only once the number of required pools for a GR close is 10 or lower will you gain the full XP benefit from a GR close. This can significantly impact your XP/hr at low paragon, so keep it in mind when planning your leveling strategy. As a rule of thumb, you should gain full XP even from GR 150 at around Paragon 1725.

This tool allows you to calculate the amount of time required to reach a desired Paragon level based on your current Paragon level, desired Paragon level, XP per hour, and hours played per day. The calculator will display the amount of XP needed to reach your goal, the number of days required, and the number of hours required. Additionally, it will generate a graph of your Paragon level progression over time until the goal is reached.