PURPLE crying is a normal developmental phase when healthy infants cry intensely, sometimes for hours, and resist all attempts at soothing. The term was created not to describe a color but as an acronym to help parents understand that this relentless crying is a predictable stage that all babies go through, not a sign that something is wrong.
What the Acronym Stands For
PURPLE is a framework developed by pediatric researchers to describe the key features of this crying phase. Each letter captures one characteristic:
- P – Peak of crying. Your baby’s crying increases over the first few months, hits a peak, then gradually decreases.
- U – Unexpected. Crying bouts can start and stop without any clear reason. There’s no hunger, wet diaper, or discomfort you can point to.
- R – Resists soothing. No matter what you try, rocking, feeding, singing, the baby keeps crying.
- P – Pain-like face. Babies often look like they’re in pain even when they’re perfectly healthy.
- L – Long-lasting. Episodes can stretch for hours at a time.
- E – Evening. Crying tends to cluster in the late afternoon and evening hours.
The acronym was designed to reframe what many parents experience as a crisis into something expected and temporary. It describes the same phenomenon that older generations called “colic” or the “witching hour.”
How It Relates to Colic
PURPLE crying and colic describe the same thing. The difference is in framing. Colic sounds like a medical diagnosis, which can make parents feel their baby is sick or that they should be able to fix it. Some pediatric experts specifically avoid the word “colic” for this reason. If your baby is growing well, feeding normally, and gaining weight but cries inconsolably every evening, they’re in their period of PURPLE crying. Nothing is broken. Nothing needs to be cured.
The traditional medical definition of colic uses the “rule of threes”: crying for more than three hours a day, more than three days a week, for more than three weeks. PURPLE crying drops this rigid threshold and instead describes a spectrum. Some babies cry more than others, but nearly all babies follow the same arc of increasing and then decreasing crying over the first several months.
When It Starts and When It Ends
Crying typically begins ramping up around 2 weeks of age. It increases steadily through the first few months, with most babies hitting their peak at about 2 months old. After that peak, the crying gradually tapers off between months 3 and 5. By the time most babies are 4 to 5 months old, the intense, inconsolable episodes have largely disappeared.
This timeline holds true across cultures. Studies of infant crying patterns around the world show the same arc regardless of parenting style, feeding method, or family structure. That consistency is one of the strongest pieces of evidence that PURPLE crying is a built-in developmental phase rather than a response to something parents are doing or not doing.
Why Babies Go Through This Phase
No one has identified a single cause. The most widely accepted explanation is that it reflects the rapid development of a baby’s nervous system during the first few months of life. A newborn’s brain is processing an enormous amount of new sensory information, and the systems that regulate stress and emotion are still immature. Crying may be the infant’s primary way of discharging that neurological overload, especially late in the day when stimulation has accumulated.
It’s not caused by gas, formula, breast milk, or anything you ate. While digestive discomfort can make babies fussy, the PURPLE crying pattern occurs in babies regardless of how they’re fed. The pain-like facial expressions that make parents sure something hurts are part of how babies cry intensely, not evidence of an underlying problem.
Why Understanding This Phase Matters
The Period of PURPLE Crying concept was developed in large part as a child safety initiative. Hours of inconsolable crying can push even loving, well-intentioned parents to a breaking point. Frustration from relentless crying is the single most common trigger for shaken baby syndrome, now more formally called abusive head trauma. When a caregiver doesn’t understand that the crying is normal and temporary, the risk of a dangerous response increases.
Educational programs built around the PURPLE framework are now delivered in hospitals and birthing centers across North America. These programs teach parents what to expect during the newborn period so they feel more prepared and less alarmed. The core message is simple: the crying is not your fault, you cannot always stop it, and it will end on its own.
What You Can Do During an Episode
You can try the standard comfort techniques: gentle rocking, skin-to-skin contact, swaddling, white noise, a pacifier, a car ride. Sometimes one of these works. Sometimes none of them do. That’s the “R” in PURPLE, and it’s the hardest part for most parents to accept. Not being able to soothe your crying baby does not mean you’re failing.
When you’ve checked that your baby is fed, dry, and safe, and nothing is working, the most important thing you can do is manage your own stress. Put the baby down in a safe sleep space (a firm, flat surface with nothing else in it), walk into another room, and take a few minutes to breathe. Call a partner, family member, or friend to take over. This isn’t giving up. It’s the strategy that pediatric safety experts specifically recommend.
The intensity of these episodes can feel isolating, especially for first-time parents. Knowing that virtually every baby goes through this, and that the peak at 2 months is the worst it will get, can make the hardest evenings more bearable. You’re not doing anything wrong. Your baby is doing exactly what babies do.