Free archery calculators
Set up your bow with
real numbers, not guesswork
Free archery calculators for arrow spine, front of centre, kinetic energy, draw length and angle compensation, built across manufacturers and not locked to one brand's shafts. Plus published spec and mod charts for 48 compound bows, and gear guides by budget tier for archers who would rather understand the setup than be sold one.
Researched from published specifications and verified owner reviews. We do not test gear in person.
Calculators
The math you cannot avoid when setting up a bow.
KE and momentum, with the 5 gr/lb safety check
Cross-manufacturer, not locked to one shaft brand
Wingspan method plus a sanity check
Front of centre with target ranges
Build up grains from components
Real fps from an IBO rating
What you should actually be pulling
Archery angle compensation chart and calculator: true horizontal distance from a treestand
Start here
Three full builds by budget, from under $750 to under $4,000
The highest-value accessory most archers can add
Paper tune, bare shaft, walk-back
Cut, insert, fletch, and what it saves
Spine by draw weight and arrow length
48 bows: IBO speed, axle to axle, draw length range and how each one adjusts
Adjustable bows that grow with you, by budget tier
Portable and bench presses, and when a bow vise is the better buy
Deer and foam targets, cheap to self-healing
Fixed blade vs mechanical, by cutting diameter and flight
Wrist strap, thumb button and hinge
Why this site exists
Almost every arrow spine and FOC calculator online is run by a shaft manufacturer, and every one of them recommends their own shafts. That is not necessarily wrong, but it is not neutral either. These tools compare across manufacturers, show their formulas, and tell you when the honest answer is that two options are equivalent.
We earn a commission if you buy through our links, at no cost to you. That never changes which product we recommend, and we say plainly when something is not worth the upgrade.