Atlas Ballistics vs Hornady 4DOF
Hornady 4DOF is the most-installed ballistics app there is, and it costs nothing. Atlas is built for everything that happens around the solve. Here is when each one is the right call.
The short answer
Choose Hornady 4DOF if
Hornady 4DOF if you want a solid free calculator, you shoot mostly Hornady factory ammunition, and a firing solution is all you need from the app.
Choose Atlas if
Atlas if the calculator is just the start — you want stage cards, timed runs, group analysis, a shot log and spotting on the same rifle profiles, and an app that opens with zero signal.
Side by side
| Feature | Atlas | Hornady 4DOF |
|---|---|---|
| Platforms | iPhone, iPad, Mac, Apple Watch, Android | iOS, Android |
| Price | Free; Pro $5.99/mo or $49.99/yr | Free, no in-app purchases |
| Bullet library | 935 bullets across makers, plus custom cartridges | Extensive, Hornady-focused |
| Truing against real impacts | Yes — MV or BC | MV truing |
| Multiple loads per rifle | Unlimited | Profile-based |
| Reticle library | 175 reticles, 22 brands, holds drawn on your glass | Not listed |
| Apple Watch | Yes — capture shot direction from the wrist | Not listed |
| Ammo box AI scanner | Yes | Not listed |
| Shot group analysis | Yes | Not listed |
| Stage cards with timed runs | Yes | Not listed |
| Shot log with photos | Yes | Not listed |
| Phone-to-phone spotting | Yes | Not listed |
| Hunting maps | Atlas Hunt, in development | Not listed |
Feature and pricing data collected August 2026 from each product’s own listing. Things change — check the source links below before deciding.
Where Atlas is different
Built for the range day, not just the math
Hornady 4DOF answers one question: what do I dial. Atlas answers that one, then keeps working — build a stage card for every position, run it on the clock, log the shot, photograph the group and get its MOA, spot your own impacts through your scope. Same rifle profiles, one app.
Opens every time, signal or not
A recurring complaint about 4DOF in shooter forums is unreliable behavior on a weak connection. The entire Atlas solver runs on your device. Mountain range with zero bars, the app opens and solves.
Every maker's bullets, plus your own
Atlas ships 935 bullets across Hornady, Berger, Sierra, Lapua, Nosler and more, and you can build a custom cartridge from scratch. Nothing in the app steers you toward one company's product line.
Every load under one rifle
Unlimited ammo profiles per rifle. Swap from your match load to your hunting load in one tap and your zero, twist and sight height stay exactly where they were.
Where Hornady 4DOF has the edge
Straight answers — a comparison you can't trust is worthless.
It is free, full stop
No in-app purchases, no subscription, nothing gated. If cost is the deciding factor and a firing solution is all you need, 4DOF is the honest recommendation and we would rather make it than dance around it.
Backed by Hornady
It comes from one of the biggest names in ammunition, with the install base to match — over 42,000 App Store ratings. If you shoot their ammunition and want their data behind your solves, that pairing makes sense.
A long track record
It has been on iOS and Android for years with a large install base, so there is plenty of community help out there if you get stuck.
Questions people ask
Is Atlas more accurate than Hornady 4DOF?
The honest answer for any two serious solvers: the math gets you close, and truing gets you exact. Atlas implements the standard models correctly and then corrects your profile from real confirmed impacts, so your solves converge on what your rifle actually does. Run both against steel at distance and keep the one that matches — that test costs nothing, since both apps are free to try.
Why pay for Atlas when 4DOF is free?
If all you want is a firing solution, maybe you should not — 4DOF is a good free calculator. Atlas earns its keep when you want the rest of the day in the same app: stage cards on a timer, group analysis from a photo, a real shot log, spotting through your own scope. And Atlas is free to use too; Pro is optional.
Does Atlas work with Hornady bullets?
Yes. Hornady projectiles are in the built-in library alongside every other major maker, and the ammo box scanner reads Hornady factory boxes.
The only test that matters is your steel
Run Atlas against what you use now — free to download, with a free plan and a free trial of Atlas Pro.
Sources
Hornady 4DOF is a trademark of Hornady Manufacturing Company. This page is not affiliated with, sponsored by, or endorsed by Hornady Manufacturing Company. Comparisons reflect publicly available information as of August 2026 and are provided to help shooters choose the right tool. If you believe anything here is inaccurate, email support@atlasballistics.com and we will correct it.
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