I, like some of you, probably noticed there's something up with Fallout 4's damage calculation. Things like Powerful/Two Shot ignoring damage
boosts from receivers/capacitators, or DOT effects seeming weaker than they should be (except Wounding, where the opposite applies) and what's up with lasers anyway?
So I thought, Hey, since I'm trying to balance this mess anyway (check out Legendary Modifier Rebalance), why not make a tool that can visually show me how this stuff works?

So I did.

The calculator can compare up to four different weapons of any type simultaneously, using fifteen-something sliders (not all of which are required, non-legendary guns can get away with as few as one to three). You can compare weapons using their ingame fire-rate (also found on Nukapedia) or on a per-shot basis.

I have also tested it against ingame conditions and found it to be about 99.9% accurate (see table in image 3 for values). The data sheet I made can be found in the Images section.

Each slider and variable has notes attached that explains what it is and what it does. For more detailed notes about each variable, check the ReadMe or download the text file under the 'downloads' tab. Don't forget to endorse if this has been useful to you.

Note: the Explosive legendary effect may deal more damage than the Pip-boy shows, since the Gunslinger and Rifleman perks also affects explosive damage for some reason, but doesn't show this on the weapon card. This effectively makes Explosive exactly like Freezing and Plasma Infused, in that it scales (using perks) with the weapon type it is attached to, be it rifles, pistols or heavy weapons.
This is integrated in the calculator and it will show the correct damage.
Also, Explosive damage is calculated as a separate hit, so if your weapon does 15 damage and the Explosive effect does 15 damage vs DR 30, a direct hit will deal 7.5+7.5=14 damage, not 15.

Update:
Corrected some spelling errors.
You may now compare four weapons simultaneously instead of three.
V 2: cleaned up the ui, corrected spelling errors, rewrote some infoboxes for clarity.

Recommended tools:
FO4Edit
Fallout 4 Configuration Tool


Recommended mods:
Unofficial Fallout 4 Patch
DLC Leveled List Integration
Settlement Attack DLC Fix

Arbitration - Better combat AI, set difficulty damage multipliers to whatever you want, player stealth is more lighting-dependent. Modular.
Hardcore Mode ON - adds a needs and diseases system that is arguably better than vanilla survival. compatible with everything and can be used on any difficulty.

Legendary Modifier Rebalance - rebalances legendary effects in an attempt to make every effect equally useful.
Realistic Guns and Bullets Overhaul - Alters weapon damage and handling to more closely match real-life ammunition and physics, so weapons using the same ammo has similar damage output. Action point cost is also overhauled, and depends on barrel length, recoil and scope use.
Weapons of Fate (Ballistics Overhaul) - Makes bullets have actual physics instead of being hitscan weapons. Leading targets and arcing at long range is now a thing.

Full Dialogue Interface - Know what you're going to say before you say it.
Valdacil's Item Sorting - Sort items by type instead of alphabetically. Options for item weight and scrap.
DEF_UI - UI improvements across the board, for Pip-boy and/or HUD.

Visible Companion Affinity - Makes it easier to keep tabs on how much your companion likes you and how much your actions affect your companion.
Scrap Grinder - Adds a scrapping workbench to the the settlement building menu for batch-scrapping junk items.
Lucky's Interesting Tips - New loading screens. Less spoilers, more lore friendly. Arguably more amusing.