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Time Management
Find Your Best Time of Day for Deep Work

Find Your Best Time of Day for Deep Work

Judy Tsuei
December 13, 2022
Updated on:
June 12, 2024

When is the best time of the day for deep work?

Find Your Best Time of Day for Deep Work
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If you find yourself struggling with productivity and dips in energy throughout the 9-5 workday, you’re not alone. While it may seem completely natural to go to work at 9 a.m. every day and come home at 5 p.m., the truth is that the concept of a full-time 8-hour workday is relatively new. That means that we’re forcing our minds to be productive during times that may not work best for us. 

You may also notice that you struggle to complete certain tasks at different times of the day. That’s because not all work is the same — for example, in a product management position, sending an email doesn’t take up the same amount of brain power as drafting a product roadmap. 

By understanding what time of the day works best for you to complete different tasks, you can increase productivity and maintain your energy levels throughout the day. 

Read on to learn more about: 

  • What deep work is and why it’s important 
  • How to work with your body to create your ideal deep work schedule 
  • The best tool for prioritizing deep work — no matter how busy you are

What is deep work?

Deep work is a concept coined by Cal Newport to describe work activities “performed in a state of distraction-free concentration that push your cognitive capabilities to their limit.” In “Deep Work: Rules for Focused Success in a Distracted World,” Newport explains that deep work often requires high levels of creativity and/or critical thinking. Examples include writing a blog post, drafting a product roadmap, or writing an expense report.

Because deep work requires a lot of energy and concentration, it can only happen successfully if you work on a task for a long block of time. Interrupting a task to check social media or do smaller tasks can pull you out of deep work mode.

In contrast, shallow work is any task that doesn’t require a lot of concentration or cognitive abilities and is easily replicated. These are tasks that you can do while distracted, which often add little value to your overall goals. Shallow work includes data entry, checking and responding to emails and Slack messages, or scheduling meetings.

What are the benefits of deep work?

Most of us spend our days performing shallow work. This is especially concerning for knowledge workers, whose workplace contributions depend on their ability to focus deeply and produce high-quality, innovative work. That said, here are three reasons to incorporate a deep work routine into your working life:

  • Sharpened skills: By definition, deep work challenges you intellectually. You might feel some friction at first, especially if your brain isn’t used to switching into deep work mode. But, with practice, you’ll notice enhanced cognitive performance, allowing you to tackle complex tasks more efficiently and effectively. 
  • Competitive advantage: In a world where distractions run rampant, the ability to engage in deep work is rare and valuable. If you can master deep work, you’ll have an edge over competitors. 
  • Greater productivity: Deep work doesn’t just improve the quality of your work; it also improves the quantity of your output. By maximizing productivity during work hours through deep work, you can be more present during your off hours, lending to better work-life balance.

Now that you know why deep work is so important, it’s time to start crafting your deep work schedule. Let’s start with a quick science lesson.

What does science say is the best time of day for deep work? 

While everybody is different, most scientists agree that people typically follow a predictable pattern that can determine when the best times to work are. According to this basic pattern, we start the day in good spirits, making the morning the perfect time for the most important tasks on your to-do list, a.k.a. deep work.

But what if you’re a night owl?

Mornings aren’t for everyone, and some people take longer than others to feel good during the day. But even if you aren’t a morning person, everyone follows the same pattern of an early peak, and an energy slump later. If you get up late, then your peak may be 3 p.m. instead of noon. As we age, too, our peak energy time changes. Adolescents are notorious late risers, and therefore have a later peak in energy, but older adults tend to be early risers.

Part of finding the best time to work is understanding the natural cycles of energy that your body goes through.

Finding the best time to work: circadian vs. ultradian rhythms 

You’ve likely heard about the circadian rhythm, but do you know about the other rhythm that dictates your energy levels? The circadian rhythm, otherwise known as our internal clock, is the body’s 24-hour cycle. It affects when we go to sleep, when we eat, and what our energy levels are throughout the day. 

On the other hand, the ultradian rhythm is a cycle that happens several times a day. Ultradian rhythms influence our energy levels and well-being, and are typically 90-120 minutes long. This includes 90 minutes of peak performance, followed by 20 minutes of rest and recovery. Your ultradian rhythm is what’s responsible for you feeling “in the zone” for an hour, and then feeling out of focus, tired, and craving a snack.

It’s important to remember that ultradian rhythms are good. So instead of panicking that you’re already losing focus by 10 a.m., remember that it’s just the end of one ultradian rhythm. Naps, walk breaks, and snacks are all great ways to rest so that your body is ready for the next cycle. Scheduling breaks in your day can also help improve your work-life balance, ensuring you have energy after work. 

Deep work is best done during the 90 minutes of peak performance in your natural ultradian rhythm. It can be tempting to fill in the tail end of the rhythm with shallow work, but remember — your body and mind need rest. And while shallow work is not as energy-intensive as deep work, it still does require energy and attention. 

How to schedule deep work for maximum productivity 

A big part of scheduling deep work is understanding how your individual energy levels fluctuate throughout the day. Start by keeping a journal and noting how you feel every hour, or every other hour.

  • Are you struggling to focus?
  • Do you feel like you need a nap or a snack?
  • When do you feel the most energized?

After a few days, you’ll begin to notice patterns. Pay special attention to when your energy peaks in the day — this will inform your ideal time for deep work. For most people, that’s between 8 a.m. and 2 p.m., but it may be different for you.

Once you’ve become familiar with your energy levels and identified your ideal time of day for deep work, it’s time to build your schedule. Thankfully, we’ve designed a tool that’ll do that for you.

Clockwise uses AI to automatically schedule your meetings, deep work, and breaks at their perfect times. Simply tell Clockwise all the elements of your ideal day — your preferred work hours, meeting hours, Focus Time goals, breaks, and more — and allow Clockwise to arrange your schedule for you.

deep work with Clockwise
Create more time to focus with Clockwise

Even better, Clockwise works for entire teams and organizations, making better time management part of your company culture. And, because it’s automatic, it’s even easier to make a plan and stick with it.


How long should deep work sessions be?

Thanks to our ultradian rhythms, 90-minute blocks of time are the most effective for deep work. 

How many deep work sessions should I do per day?

Cal Newport outlines four philosophies of deep work, each offering a different approach to integrating deep work into your work schedule.

  • With the monastic philosophy, you dedicate nearly all of your time to eliminating distractions and engaging in deep work.
  • Not as all-in as monastic, the bimodal philosophy divides your time between deep and shallow work. You might allocate months, weeks, or days to each mode, but never less than a day.
  • The rhythmic philosophy incorporates deep work sessions into your daily routine. This philosophy pairs well with a productivity technique like time blocking or the Pomodoro Technique.
  • Lastly, the journalistic philosophy is all about performing deep work whenever you can, with no consistent schedule. 

The number of deep work sessions you should perform each day depends on which philosophy you practice. Monastic and bimodal philosophies involve full-day sessions, rhythmic philosophy typically includes at least one 90-minute session each day, and the journalistic approach has no set number.

How do I get into deep work?

For your best chance at getting into deep work mode, it’s important to eliminate all distractions. Give yourself permission to close your email tab, silence notifications, and focus on a single task. Try out different types of focus music (lo-fi, classical, nature) to find out which is most conducive for your concentration.

Pro tip: The Clockwise for Slack app automatically mutes your Slack notifications whenever you’re in a meeting or engaged in a Focus Time block — perfect for getting into deep work and finding your flow. 

How do I schedule deep work?

Fitting deep work into your calendar can feel like a game of Tetris, especially if meetings tend to overcrowd your workday. That’s why we created Clockwise. This AI-powered calendar assistant automatically schedules and protects Focus Time, while optimizing your meetings for their ideal times. 

Just enter your weekly Focus Time goals, then let Clockwise handle the scheduling for you. Compatible with both Outlook and Google Calendar.

Going forward 

Deep work is an essential part of our workday. It’s when high-value, creative tasks get done. It’s important to schedule deep work for times of the day where we have the highest energy levels and are at peak cognitive performance. Follow these tips to design a schedule that works with your natural energy levels. 

Clockwise can help you create your ideal deep work schedule, increase productivity, and coordinate with your team. Get started for free!

About the author

Judy Tsuei

Judy Tsuei is a Simon & Schuster author, speaker, and podcast host. She has been writing for Clockwise for several years while also being featured in MindBodyGreen, BBC Travel, Fast Company, Hello Giggles, and more. As the founder of Wild Hearted Words, a creative marketing agency for global brands, Judy is also a mentor with the Founder Institute, the world's largest pre-seed accelerator. Judy advocates for mental and emotional health on her popular podcast, F*ck Saving Face. Follow along her journey at

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