Best Fasting Tracker App for Gym Workouts (2026)

For lifters who want to time a fasting window without splitting their gym and food records across more apps, PeakBFF is the best fit. It has selectable fasting schedules, a live timer, a completion reminder, and a history of ended fasts beside its workout log and nutrition tools. It records the window you choose. It does not tell you whether fasting is right for you or how you should train.

Short answer: choose PeakBFF when a fasting timer needs to live beside the sets, reps, food, protein, and macro entries you already choose to log. Zero is a strong option for a fasting-first app with plans, history, and educational content. Fastic suits people who want fasting, food, water, and step tracking in a weight-management-focused app. Simple is worth a look if tailored fasting and meal guidance are the central reason you want an app.

The 4 apps, compared

Fasting is not automatically appropriate for every person or training goal. If you are pregnant, under 18, managing a medical condition, have a history of disordered eating, or use medication affected by food intake, get individual guidance from a qualified clinician before changing your eating pattern. Stop and get help if a plan makes you feel unwell.

1. PeakBFF

PeakBFF makes the most sense when your question is not only "how long have I been fasting?" but also "what did I actually log around this gym day?" Choose a 16:8, 18:6, 20:4, OMAD, or custom window, start the timer, and see elapsed and remaining time. When you finish, the history keeps the duration, starting date, selected protocol, and whether the chosen target was completed.

That is deliberately a simple record. A timer cannot decide whether you need to eat before training, assess your recovery, or turn a fasting streak into a measure of workout quality. What it can do is keep a time window near the other records that make a gym day easier to review: completed sets and reps, plus food, calorie, protein, or macro entries when you choose to save them.

The optional completion reminder is useful when a timer is the one thing you do not want to keep checking during work, travel, or a training session. It is not a prompt to keep fasting past your own plan or comfort level.

If keeping the meal side of the record is your main priority, our comparison of the best apps to track workouts and macros shows how that broader choice differs from a fasting-first app.

Best for: lifters who want to log a chosen fasting window alongside their workout and nutrition record, without treating the timer as coaching.

2. Zero

Zero is the established fasting-first choice in this group. Its public materials describe popular and custom fasts, an advanced timer, fast history, average fasting length, streaks, and expert content. Its current App Store listing also describes meal, protein, and hydration tools.

That is a thoughtful fit when the fasting practice itself is the center of the app you want to use. It gives people more fasting-specific content and a deeper focus on plans than a gym log needs to provide. The trade-off for a lifter is that strength-session logging is not the focus of Zero's public fasting tools.

Choose Zero when fasting plans, fasting education, and long-term fasting statistics are the job. Choose PeakBFF when you would rather keep the timer close to a conventional gym session and the food record you are already making.

Best for: people who want a fasting-first app with plans, learning content, and detailed fasting history.

3. Fastic

Fastic presents a wide fasting and weight-management toolkit. Its current site describes tracking fasting times and body status, plus water, food, step, and meal trackers. It also offers habit content and recipes, which can be useful for people who want a guided routine around the timer.

Fastic is a reasonable pick if fasting, meals, water, steps, and lifestyle content all belong in the same experience. That is a different job from a weightlifting log where the useful record is the actual load and reps from a session. Fastic's public positioning does not make a strength-workout log the main reason to choose it.

Choose Fastic when the broader fasting lifestyle toolkit is what you want. Choose PeakBFF when a straightforward fasting history and your completed gym sets need to sit in one app.

Best for: people looking for a fasting timer with food, water, step, and habit-tracking tools.

4. Simple

Simple combines a fasting tracker with meal logging, hydration, movement tracking, and tailored guidance. Its help center describes a Track tab where users can review logged fasts and food by day, see the active fasting window, and log meals. It also positions coaching and guidance as part of the experience.

That can be appealing if you are looking for a guided program around fasting and meals. Simple is more prescriptive in feel than a basic log. Its public materials describe movement and activity tracking, but they do not present a strength-session log for working weights and reps as the core feature.

Choose Simple when guided fasting and meal support are the decision. Choose PeakBFF when you want a timer and history that complement the gym work you already log yourself.

Best for: people who want guided fasting and meal support in the same tracker.

What lifters should check in a fasting tracker

The best choice depends on the record you want to look back at, not on the longest possible timer.

1. Can you set a realistic window? Look for the schedules you can actually use, or a custom option when a preset does not match your day. A timer is a record of a choice, not a challenge to extend.
2. Can you see the history clearly? A start date, duration, and selected protocol are enough to spot the pattern you have actually kept. Do not read a streak as a health or training score.
3. Does it fit your real gym log? If you track weight and reps, make sure the fasting app does not create another place you need to reconcile later.
4. Does food context matter to you? Meal, protein, water, and macro tools can be useful when you want one chosen daily record. They do not determine what you personally should eat.
5. Are the prompts appropriate? Check reminders and guidance before you commit. You should be able to end or change a plan when your circumstances call for it.

For a simple log that makes the training side easier to review, see our guide to tracking exercise history in the gym.

The bottom line

Zero is a capable fasting-first app, Fastic offers a wider fasting lifestyle toolkit, and Simple is a solid choice when guided fasting and meals are the focus. They are all reasonable tools for different jobs.

For most lifters who want to keep a chosen fasting window near the workouts, food, protein, and macros they already record, PeakBFF is the better fit. It keeps the timer and fast history practical without pretending to prescribe a diet or judge a training session. Download PeakBFF on the App Store or Google Play and start with the record you can use consistently.