Understanding your 'window of tolerance'

Uncover the framework of your optimised emotional state, so you can see more clearly when, or why, the stresses of everyday life might become overwhelming

We’ve all had that moment: you’re running late, juggling the morning routine, and suddenly your coffee spills everywhere. It feels like the universe is against you. On a calm day, this might lead to a quick exhale of frustration, but you’d carry on. Yet, this very same scenario can result in a completely different reaction on a day when you’re already stressed, making this small mishap feel like the straw that breaks the camel’s back. Suddenly, you can find yourself angry, overwhelmed, or even tearful.

This example highlights what’s known as the ‘window of tolerance’, a term introduced by Dr Dan Siegel to describe our personal comfort zone where we feel calm, grounded, and in control of our emotions. It’s the space where we’re able to face challenges, think clearly, and respond thoughtfully. When stress pushes us out of this zone, it can lead to emotional overwhelm.

However, our window of tolerance is not fixed. It can expand or shrink depending on various factors like stress, fatigue, hormonal changes, life events, or even past trauma. These influences shift our emotional state, pulling us outside our window of tolerance into dysregulation. Initially, this might feel like mild discomfort or restlessness, but if not addressed, we can move into hyperarousal or hypoarousal.

Hyperarousal is where we feel anxious, reactive, overwhelmed, or angry – think of it like the action-driven fight-or-flight responses. Alternatively, we may slip into hypoarousal, which is characterised by numbness, emotional shutdown, or disconnection – also known as a freeze response.

The key to managing emotional dysregulation lies in awareness. By noticing when we are moving outside our window of tolerance, we can intervene early. The first signs of dysregulation may show up physically, such as with shallow breathing, a racing heart, tight muscles, or an uneasy stomach. These are all cues that we can learn to tune-in to. Once we notice them, we can use grounding techniques to restore a sense of calm. Before learning about this idea, many people do not have awareness of what they are experiencing, which makes it difficult to self-regulate because they don’t even know it is happening.

I have found that introducing the idea of a window of tolerance to my clients has been invaluable in helping many to understand why they might feel they overreact to a situation, or why they often feel overwhelmed. This understanding can reduce feelings of inadequacy or shame, and promote self-compassion.

It’s also important to recognise that the stressors impacting our window of tolerance are not always obvious. We probably know when we’re stressed about a work deadline, or money worries, but the roots of our dysregulation often run deeper. Past trauma, whether our own or inherited, can play a significant role in shaping our emotional responses, often out of our awareness.

Trauma can manifest in patterns of behaviour and emotional responses that get passed down through generations. If you grew up in an environment where emotional regulation was difficult, or dysfunctional coping strategies were modelled, you might adopt these same patterns. As a result, your window of tolerance can be small, because your emotional system is already primed to react in a particular way.

Recognising that our emotional responses may be rooted in these inherited patterns can help us to start the process of releasing ourselves from these automatic responses. By expanding our window of tolerance, we create space for healthier emotional responses to stress, enabling us to feel calmer and more resilient.