Tools

Marathon Planner (VDOT / Jack Daniels)

Jack Daniels is one of the most respected coaches in running. His VDOT system estimates your fitness from a race result and translates it into five training intensities: E, M, T, I, and R. Enter your goal marathon time and current training data below to get your VDOT, training paces, and a four-phase plan outline: Base, Threshold, Marathon Specific, and Taper. The tool is useful for first-time marathoners and experienced runners alike.

Your data

Inputs for the VDOT estimate and plan outline.

Race dateGoal time (hh:mm:ss)Weekly running volume (km)Current long run (km)Running days / weekExperience level

Warnings

No race date selected. Using the default plan length.

Output

Calculations ready.

Weeks to race

18 wk

Plan: 18 weeks.

Marathon pace

5:20 /km

Goal: 03:45:00

VDOT

Peak weekly km

Long run target: 30 km

Training paces (Daniels)

E (Easy)

5:44 /km – 6:51 /km

Easy pace. Conversational, controlled, and the backbone of weekly volume.

M (Marathon pace)

5:11 /km – 5:40 /km

Marathon pace and work close to it.

T (Threshold)

5:00 /km – 5:14 /km

Threshold pace. Comfortably hard, usually in 10-20 min blocks with short recovery.

I (Interval)

4:30 /km – 4:42 /km

VO2max-oriented intervals of 3-5 min, with jog recoveries roughly equal to the work.

R (Repetition)

4:07 /km – 4:20 /km

Short, fast work for economy and mechanics, with full recovery.

Plan phases

Four-phase Daniels structure: Base, Threshold, Marathon Specific, Taper.

Phase I: Base (E + strides)

5 wk

Build aerobic volume, mechanics, and durability. Plenty of E running, strides, and basic running strength.

Long run 24-24 km at E (5:44 /km or slower).
6-10 strides of 15-20 s after E runs, with full recovery between reps.
One light T session per week, e.g. 2 x 10-12 min at T (5:00 /km).

Phase II: Threshold (T emphasis)

5 wk

Build threshold and pace control, while gradually adding M work.

T: 3 x 10-12 min or 2 x 20 min at T (5:00 /km), with 2-3 min jog recovery.
Long run 26-30 km with a slightly faster finish (steady).
One M session, e.g. 6-12 km at M (5:11 /km) in the middle of a run.

Phase III: Marathon Specific (M focus)

5 wk

Longer M segments inside long runs, while maintaining T and adding a small touch of I.

Long run 26-30 km with 2 x (5-8 km) at M (5:11 /km) or 12-18 km continuous at M for advanced runners.
T maintenance: 2 x 15 min or 3 x 10 min at T (5:00 /km).
Optional I session: 5-6 x 1 km at I (4:30 /km), with 2-3 min jog recovery.

Taper

3 wk

Reduce volume while keeping the stimulus. Freshness matters more than heroics.

Shortened long run 16-22 km with 6-10 km at M (5:11 /km).
Short T session: 2 x 10 min or 20 min continuous at T (5:00 /km).
6-8 strides of 15-20 s, plus plenty of sleep and race-day nutrition testing.

Note

Daniels works best when you respect the VDOT paces and resist turning every run into a workout. Most of your weekly volume is E, and quality sits in Q1/Q2. Simple, disciplined, effective.

Weekly structure (Daniels)

5 days / wk

Q1 (quality session 1)

Usually T work or M blocks inside a continuous run.

Q2 (quality session 2 / long run)

Long run with progressive growth up to 30 km. In Phase III: M segments.

E runs (weekly base)

Everything else is E. It is not filler; it is the foundation. Add strides 2-3x per week.

Strength + mobility

2 short sessions (20-35 min): core, glutes, calves, feet. Consistency beats heroics.

Training plans

Go beyond paces with a full training plan

Training paces are a starting point. A personalized trail plan adapts intensities to mountain terrain and race demands.

Build your plan

Free preview included

Recommended gear

Energy Gels

Fast-absorbing fuel for sustained effort over long distances.

View on Amazon→

Electrolyte Mix

Sodium, potassium, and magnesium to maintain hydration under load.

View on Amazon→

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Marathon Planner (VDOT / Jack Daniels)

Your data

Output

Plan phases

Weekly structure (Daniels)

Go beyond paces with a full training plan

Energy Gels

Electrolyte Mix

Your data

Output

Plan phases

Weekly structure (Daniels)

Go beyond paces with a full training plan

Energy Gels

Electrolyte Mix

Science-backed notes on training, recovery, and racing smarter in the mountains