Trusted by athletes who train
Marathoners
Cyclists
Triathletes
Trail runners
Track clubs
01The problem
Stop checking three apps.
Get one score.
Weather apps show data. Strava shows weather after you run. Zeph tells you when to go before you lace up — one number, tuned to your sport.
Without Zeph
✕Weather.app · Strava · UV index
✕Guess: 68° + 80% humidity vs 72° + wind?
✕Mentally calculate "best window"
✕End up running at lunch anyway
With Zeph
✓"Run at 6:30 AM — Score: 9"
✓7 factors, weighed by sport science
✓Get notified when window opens
✓Train at peak. Then get on with your day.
02Live demo
Find your perfect window.
Hour by hour.
Drag the slider. Watch the score and recommendation update in real time. This is what your morning looks like inside Zeph.
03Tuned to your sport
A cyclist's perfect day
isn't a runner's.
75°F at 80% humidity is brutal for a tempo run, fine on the bike. Zeph adjusts every threshold — heat tolerance, wind resistance, UV exposure — to match how your body actually responds.
04Inside the app
Built like a coach.
Not a dashboard.
Every screen pushes toward one decision. No data slop. No mental math. Just the answer.
01
Today's score
One number. One window. The home screen tells you everything in three seconds.
02
Plan your week
See every day at a glance. Saturday's a 10. Plan the long run there.
03
Pick your top 3
Switch between sports with a tap. Each one re-scores against its own thresholds.
04
Your tolerances
Set the temperature, training hours, and intensity rules that match how you train.
05
Briefings & alerts
Morning summary at 7. Push 30 minutes before your window opens. Your call.
05How it works
Three taps to a smarter workout.
06Pricing
Simple, transparent pricing.
7-day free trial. Cancel anytime. No hidden fees.
Monthly
$4.99
/month
Never miss your ideal workout window.
Start 7-day free trial →
✓7-day free trial
✓Check conditions anytime
✓Run, cycle, walk, HIIT
✓7-day weather outlook
✓Smart window alerts
✓Morning briefings
BEST VALUE
Annual
$39.99
/year
~ $3.33/month
Never miss your ideal workout window.
Start 7-day free trial →
✓7-day free trial
✓Check conditions anytime
✓Run, cycle, walk, HIIT
✓7-day weather outlook
✓Smart window alerts
✓Morning briefings
Cancel anytime in 2 taps. No questions asked.
How is this different from a regular weather app?+
Most weather apps show raw data. Zeph interprets it for athletic performance — every weather factor combined with your specific sport gives a single 0–10 score and the exact best time to train.
Doesn't Strava already show weather data?+
Strava shows weather after your workout for context. Zeph tells you when to go before you lace up. Think of it as the difference between a post-workout report card and a pre-workout coach.
Does Zeph use my location?+
Only with your permission, and only to fetch weather for where you are. Location stays on your device — we never sell it, share it, or store it on a server.
Does it work without cell service?+
Zeph caches your latest forecast, so the score and window stay readable offline. To refresh conditions, you'll need a connection.
What notifications can I receive from Zeph?+
Two kinds: a Morning Briefing (daily summary at your chosen time) and Window Alerts (15, 30, or 60 minutes before your optimal window). Both are opt-in and customizable.
What sports does Zeph support?+
Running, trail running, cycling, walking, hiking, swimming, yoga, HIIT, and a general outdoor profile. Each has its own thresholds for heat, wind, UV, and humidity tolerance — the same conditions score differently across sports.
Is there a free version?+
7-day free trial with full features. After that, $4.99/month or $39.99/year (save 33%). Cancel anytime in two taps.
Does Zeph work outside the US?+
Yes. Anywhere your phone has location and weather data, Zeph works.