Reckon is a lightweight, "Details!" inspired live damage and healing meter for The Elder Scrolls Online. It shows your own DPS and HPS accurately, breaks the group down player-by-player when your groupmates are sharing data, and fills in the rest with a smart estimate.

Features

Accurate personal DPS/HPS: read straight from your own combat events, including pet and companion damage.
Per-player breakdown: a class-coloured bar with the real character name for every group member running Hodor Reflexes or any LibGroupCombatStats addon.
Smart "Unknown" estimate: for players who aren't sharing, Reckon estimates the remainder from the target's health, so you still get a read on the whole group.
Healing mode: switch to HPS and see effective healing for everyone sharing.
Per-ability drill-down: click your own bar to see your abilities ranked by damage or healing.
Clean Details!-style look: class colours, ranked bars scaled to the top performer, a settings cog, and a dark frame that stays out of the way.
Updates live during combat, with an optional end-of-fight summary printed to chat.

Installation

Download the latest file and unzip it.
Put the Reckon folder into your AddOns directory:
- Windows: Documents\Elder Scrolls Online\live\AddOns\
- Mac: ~/Documents/Elder Scrolls Online/live/AddOns/
Launch ESO, open Add-Ons from the menu, enable Reckon, and reload the UI (/reloadui).
Type /reckon test in chat to preview the window, then drag it into place by its title bar.

LibAddonMenu-2.0 is bundled, so the settings panel works immediately with nothing extra to install.

Dependencies (only for per-player numbers)

Reckon runs on its own in group-estimate mode with no extra downloads. To see each group member individually, you and your groupmates need these libraries. The easiest way to install is through Minion:

LibGroupCombatStats
LibCombat
LibGroupBroadcast

These are the same libraries Hodor Reflexes uses, so most trial and dungeon players already have them. Type /reckon status in-game to check whether they're detected.

How to use

/reckon show or hide the window
Click the cog (top-right) for settings, or type /reckon settings
/reckon mode switch per-player ⟷ group estimate
/reckon heal switch damage ⟷ healing
Click your bar open your per-ability breakdown (click again, or right-click, to go back)
/reckon resetdelay <seconds> how long the meter holds the result between pulls
Drag the window by its title bar

Compatibility

Works alongside Hodor Reflexes and any LibGroupCombatStats addon. Reckon reads the same shared data.
Shares data only through LibGroupCombatStats (the sanctioned, rate-limited channel), so it won't cause the disconnects that older overlapping damage-sharers could.
PC and Mac only ESO does not support custom add-ons on console.

Good to know

Exact numbers for other players are only possible while they're sharing; otherwise ESO never sends their detailed combat data to your client, and the "Unknown" estimate covers the rest.
The group estimate is meaningful on a boss or a target dummy, and unreliable on trash or multiple targets at once.

Source code and full changelog: GitHub