🏹 Archery KE Calculator

Calculate total arrow weight, kinetic energy, momentum, FOC, and estimated downrange energy retention using your finished hunting arrow, selected broadhead, and measured FPS.

Version 1.0.3

Bow setup

Use your measured setup values. This version assumes a Nock On style rear build with 4 Max Stealth vanes at 2.5-degree right helical as the standard configuration.

Reference value for grains-per-pound and setup context.
Throat of nock to end of shaft.
Include shaft, insert, collar, nock, wrap, and the standard 4 Max Stealth vane set if they are already in your measured weight.
Selecting a broadhead updates weight and profile automatically.
Weight follows the selected broadhead automatically.
Use chronographed FPS for the exact finished hunting arrow and broadhead.
Measure from the throat of the nock to the arrow balance point to calculate FOC.

Broadhead and rear-build profile

This panel ties the chosen head to blade style, intended use, and the default rear steering setup for the calculator.

G5 T2

John Dudley collaboration 2-blade expandable built for a compact 100-grain mechanical option.

Mechanical 100 gr Deer to elk 4 Max Stealth vanes 2.5° right helical 36 gr vane package
FOC, drop-off table, and game setup guidance update automatically.

Results

Total arrow weight
0 gr
Kinetic energy
0 ft-lbs
Momentum
0 slug-ft/s
Grains per pound
0 gpp
FOC
0%

Distance and energy drop-off

Estimated values at 30-yard increments through 120 yards. These are modeled projections for comparison, not substitutes for chronograph testing at distance.

DistanceEstimated FPSKEMomentumEnergy dropKE retained

The distance table uses a simple drag estimate so you can compare setups consistently. Real-world loss depends on shaft diameter, vane drag, broadhead profile, altitude, and weather.

Nock On game group setups

These recommendations organize game categories around Nock On style priorities: accuracy first, compact broadheads when possible, added front weight through inserts, and arrow choice based on shot distance, wind, and animal size.

Small game and turkey

Favor speed, forgiveness, and compact steering surfaces when shots may be quick and animals move often.

  • Recommended arrow family: Sonic KE or 5.0 style lightweight build.
  • Front weight target: 50 to 75 grain insert plus 100 grain head.
  • Rear build standard: 4 Max Stealth vanes at 2.5-degree helical.

Medium game

This is the broadest category and fits the common deer and antelope use case where speed and practical field accuracy both matter.

  • Recommended arrow family: Axis, Sonic KE, or 5.0.
  • Front weight target: 75 grain brass insert with compact 100 grain broadhead.
  • Rear build standard: 4 Max Stealth vanes at 2.5-degree helical.

Large game

Move toward tougher shafts, more penetration bias, and stable fixed-blade control when hunting elk-sized animals.

  • Recommended arrow family: Axis or 5.0 for versatile western hunting; FMJ when range is shorter and penetration is prioritized.
  • Front weight target: 75 grain insert with 100 grain head, or heavier front build if tune remains clean.
  • Rear build standard: 4 Max Stealth vanes at 2.5-degree helical.

Heavy game

Use a heavier arrow philosophy where close-range penetration matters more than a flat trajectory.

  • Recommended arrow family: FMJ or another heavier high-momentum arrow with strong front loading.
  • Front weight target: heavy insert system with strong fixed head and elevated FOC.
  • Rear build standard: 4 Max Stealth vanes at 2.5-degree helical.
Game groupNock On style arrow setupBroadhead approachTypical animalsSetup intent
Small game and turkeySonic KE or 5.0, lighter shaft with 50 to 75 grain front insert and standard 4-fletch Max Stealth rear build.Compact 100 grain head for tune and fast steering.Turkey, rabbit, squirrel where legal.Speed, quick range forgiveness, and lower wind drift.
Medium gameAxis, Sonic KE, or 5.0 with 75 grain brass insert, balanced total weight, and the same standard 4-fletch rear build.Compact 100 grain broadhead, mechanical or fixed if tuned well.Whitetail, antelope, mule deer.Accuracy first, flexible for mixed distances.
Large gameAxis or 5.0 for western versatility, FMJ when penetration bias matters, with a stable 4 Max Stealth rear profile.Strong fixed blade or tuned compact head with added front weight.Elk, red deer, wild boar, black bear.More penetration and better broadhead control on heavier animals.
Heavy gameFMJ or other heavier high-momentum arrow with substantial front loading, elevated FOC, and the same 4-fletch Max Stealth helical setup.Durable fixed blade with weight-forward build.Moose, buffalo, eland.Close-range maximum penetration over trajectory.

This section follows Nock On guidance that accuracy, arrow consistency, straightness, and practical tuning matter more than chasing a single KE number.

Version history

Track updates to the calculator so changes to formulas, category guidance, and broadhead integration stay easy to review.

VersionDateChanges
1.0.32026-10-20Added FOC input and calculation, standardized the rear build around 4 Max Stealth vanes at 2.5-degree right helical, and removed all reliance on manual broadhead weight entry.
1.0.22026-10-20Integrated selectable broadheads with profile display and replaced generic game guidance with Nock On style arrow setup recommendations by game group.
1.0.12026-10-20Added broadhead-specific input handling, 30-yard drop-off table through 120 yards, game recommendation categories, and animal guidance table.

Use the next version number for future revisions so the file can act as its own lightweight change log.