RUNNERS TOOLBOX
Free running tools & calculators
Pace, training zones, race predictions and race-day planning, all in one place.
Free to use
No sign-up
Works on your phone
Free running tools
Free tools to help you train smarter and race with more confidence — from your first Couch to 5K to chasing a marathon PB. No registration, no downloads, no hidden costs.
Pace & conversions
Quick answers to everyday pace, distance and speed questions.
Quick Converter
Switch between miles, km, pace and speed in seconds — no maths required.
Miles, km, pace & speed conversions.
- Miles ↔ km
- Min/mile ↔ min/km pace
- Mph ↔ kph speed
Pace Calculator
Convert between pace, speed and finish time in seconds.
Convert pace, speed & finish time.
- Pace from finish time
- Finish time from pace
- Mile & km conversion
Pacing Table
A full searchable pace reference table, from easy to fast.
Searchable pace reference table.
- Race planning
- Training sessions
- Printable reference
Training
Get the effort right on every run, from easy days to intervals.
Training Paces Calculator
The right pace for every type of run, based on your current fitness.
Paces for every type of run.
- Easy & long run pace
- Tempo & threshold pace
- Interval pace
Heart Rate Zone Calculator
Find your training zones for recovery, tempo, threshold and VO2 max efforts.
Find your heart rate training zones.
- Karvonen or %-max method
- 5 training zones
- Bpm ranges for every effort
Predict & compare
See what you could run, and how your times stack up.
Race Time Predictor
Predict your equivalent race times across every distance from one recent result.
Predict race times from one result.
- Predict race times
- Set realistic goals
- Plan future races
Age-Graded Calculator
See how your time compares across age and gender, and what it's worth at other distances.
Compare your time by age & distance.
- Age & gender adjusted
- USATF/WMA standard tables
- Compare across distances
Race-day planning
Pacing, fuelling and weather: plan the day before you toe the line.
Race-Day Split Planner
Even, negative or positive splits for your goal time — plus a printable race band.
Splits & pacing band for race day.
- Mile & km split tables
- Printable wrist race band
- Any pacing strategy
Fuelling & Hydration Calculator
Carbs, fluid and sodium targets per hour, based on your run and conditions.
Fuelling & hydration per hour.
- Carbs per hour
- Fluid for hot conditions
- Practical gel/bottle counts
Race Weather & Heat Adjustment Calculator
Adjust your goal pace for race-day heat and humidity, so you don't blow up in the back half.
Adjust pace for race-day heat.
- Heat-adjusted pace
- Heat-stress risk flag
- Time added by distance
Why use these tools?
As an England Athletics qualified running coach, I regularly help runners answer questions like:
- What pace should my easy runs be?
- Can I break 4 hours in the marathon?
- How fast do I need to run each mile?
- What's the best pacing strategy for my race?
- How do I avoid starting too quickly?
These tools answer those questions instantly, so you can train with more confidence and make better-informed decisions — whatever your ability.
Train smarter with personal coaching
These tools are a great starting point, but personalised coaching helps you unlock even more. If you'd like a structured plan and one-to-one support tailored to your goals, I'd love to help.
Explore coaching services →Want more than the numbers?
The tools give you the numbers. A coach helps you use them, with a plan built around your goals and your week.