How often should you weigh yourself?

Some people step on the scale every morning. Others keep it in a closet and pull it out once a month, braced for bad news. If you've ever wondered how often should I weigh myself, or whether you should weigh yourself every day at all, you've probably heard both answers from people who sound very sure. The research is clearer than the arguments suggest, and it depends on what you want the scale to do for you.

The stakes are real. The scale is one of the few health numbers you can check every day, and how you use it can keep a plan on track or quietly end it. Weigh too rarely and a few pounds can creep back before you notice. Treat every daily wiggle as a verdict and a normal salty dinner starts to look like failure.

This page covers what the self-weighing trials found, daily against weekly, for losing weight and for keeping it off. Then it covers the best time and conditions for a weigh-in, how to read the trend, and the people for whom the scale does more harm than good. Why the number moves in the first place is covered in our article on how much weight fluctuates in a day.

How Often Should I Weigh Myself? A Quick Answer by Goal

How often to weigh yourself depends on what you're using the number for. The evidence behind each answer follows the list.

• Losing weight: weigh daily or on most days, at the same time each morning, and compare weekly averages.
• Keeping weight off: keep weighing daily or several times a week. When the habit fades, regain tends to follow.
• Preventing slow gain: weigh at least weekly, and daily if you can keep it neutral. The trial that prevented gain in young adults used frequent weighing.
• If the number ruins your day: weigh weekly, or put the scale away for a while and track other measures.
• If you've had an eating disorder: talk with your doctor or therapist before you weigh at all.

Should You Weigh Yourself Every Day? What the Trials Show

Yes, for most adults trying to lose weight, as long as the number is part of a plan. The randomized trials draw a clear line between a scale on its own, a scale with feedback, and a scale built into a full program.

A scale on its own

Handing someone a scale does very little by itself. In a trial of 183 adults with obesity from two English family practices, being given a scale and told to weigh daily added about 0.5 kg of extra weight loss over three months, a difference small enough to be chance (Madigan and colleagues, 2014). Both groups had the same two brief weight-loss consultations. The control group simply didn't get a scale. By the end, about three quarters of the scale group were still weighing at least weekly, so the habit stuck even though the extra loss was small.

A scale with a trend line

Adding visual feedback made a modest difference. In a two-year trial of 162 adults, daily weighing with a graph that drew a target line 1 percent below each person's current weight produced a 2.6 kg loss in the first year, against 0.5 kg in controls (Pacanowski and Levitsky, 2015). In the second year, the weighers held their loss almost exactly, and the control group, now given the same tool, lost a similar amount.

A scale inside a program

The biggest effects came when daily weighing anchored a full program. In Steinberg's six-month trial of 91 adults, the intervention group got a connected scale, a web graph of their trend, weekly emailed lessons on weight control and weekly tailored feedback on their weighing and progress. They weighed on about 6 days a week and lost 6.55 percent of their body weight, against 0.35 percent in controls. Among them, 42.6 percent reached a 5 percent loss, compared with 6.8 percent of controls.

They didn't find daily weighing miserable either. On an 8-point scale, they rated it easy to do (6.9) and helpful (6.9), and gave it low scores for frustration (2.4) and anxiety (3.1).

Reviews of the wider research agree. In one systematic review, 11 of 12 studies linked more frequent self-weighing with more weight loss or less weight gain (VanWormer and colleagues, 2008). A later review of 17 prospective studies reached the same conclusion and found no link with depression or anxiety (Zheng and colleagues, 2015).

Is It Better to Weigh Yourself Daily or Weekly?

Daily is better if you can keep it neutral. In a 12-month weight-loss program of 148 adults, people who weighed more than 6 days a week throughout lost 10.2 percent of their body weight by six months. Those whose weighing drifted down to about twice a week lost 5.5 percent, and those who eventually stopped weighing altogether lost 2.0 percent (Zheng and colleagues, 2016).

Outside any program the gap is smaller, but it's still there. In the 1,041 smart-scale owners from the Health eHeart Study, the people who kept weighing on six or more days a week lost about 1.7 percent of their weight over a year, while people who weighed about once a week from the start didn't lose any. Two groups that began by weighing almost every day and then cut back lost about as much as the daily group.

Within one trial, weighing every day also beat weighing on most days. In the intervention arm of the smart-scale trial, the 24 people who weighed every day lost 6.1 kg more over six months than those who weighed about five days a week, and they adopted more weight-control habits (Steinberg and colleagues, 2015). People chose how often to weigh in that comparison, so it shows an association rather than proof.

A weekly weigh-in is still far better than guessing. If daily readings make you tense, weigh on the same morning each week. Just know that a single weekly number is more exposed to a salty dinner or a weekend than an average of several mornings.

How Often Should You Weigh Yourself When Dieting?

When you're dieting, weigh daily or on most days. That's the pattern in the programs above that produced meaningful loss, and it's how you spot a stall in two weeks instead of two months.

Keeping the weight off

The habit matters even more once the weight is off. In the STOP Regain trial, 314 adults who had lost an average of 19.3 kg were randomly assigned to newsletters or to a program built on daily weighing, delivered face to face or online. Over 18 months, 72.4 percent of the newsletter group regained 2.3 kg or more, against 45.7 percent of the face-to-face group and 54.8 percent of the online group. Daily weighing was linked to a lower risk of regain (Wing and colleagues, 2006).

The same pattern shows up in people who kept weight off on their own. The National Weight Control Registry tracks adults who have lost at least 30 pounds and kept it off for a year or more. Among 3,003 of them, those whose weighing became less frequent gained 4.0 kg over the next year, against 1.1 kg for those who weighed more often and 1.8 kg for those who held steady (Butryn and colleagues, 2007). Gaps matter too. In daily weigh-in records from 40 adults in a health program, weight tended to fall during stretches of daily weighing, and breaks longer than a month carried a risk of weight gain (Helander and colleagues, 2014).

Preventing slow weight gain

Frequent weighing also helped young adults who weren't trying to lose much at all. The SNAP trial followed 599 adults aged 18 to 35 for about three years. Both self-regulation programs, built around frequent weighing, beat the control group. Controls gained 0.26 kg on average, the small-changes group lost 0.56 kg and the large-changes group lost 2.37 kg, and new cases of obesity fell from 16.9 percent in controls to about 8 percent in each program (Wing and colleagues, 2016).

What Is the Best Time to Weigh Yourself?

The best time to weigh yourself is first thing in the morning, after you use the bathroom and before you eat or drink, in the same clothes each time or none at all. If you've wondered when you should weigh yourself for the most comparable number, that's it. It removes most of the food and fluid that pile up during the day, and it's how the trend-line trial above asked people to weigh: first thing in the morning, under the same conditions every day.

Is your true weight in the morning or at night?

Neither one is truer, but the morning is far more consistent. An evening reading carries the day's meals and drinks, and how much depends on what you ate and when. The morning reading has had a night to clear most of that, so morning numbers compare cleanly with each other. Never judge a night weigh-in against a morning one.

Before or after exercise?

Before. A workout takes water off in sweat, so a reading straight afterward flatters you until you drink it back. If you train in the morning, weigh first and train after.

When to weigh yourself after your period

If you menstruate, the cleanest comparison is the same point in each cycle. Weight tends to run highest around a period, so compare a weigh-in from a few days after it ends with the same day of your last cycle, not with last week.

Same scale, same clothes, same spot

Clothes add more than people expect. When researchers weighed 50 adults four times over a year, with and without clothes, clothing averaged 1.2 kg for men and 0.8 kg for women, and it shifted with the season (Whigham and colleagues, 2013). That's one reason a doctor's office scale, with you fully dressed, reads higher than your bathroom scale.

Use one scale and leave it in one place on a hard, level floor. When researchers checked 61 home bathroom scales against certified weights, the digital ones were accurate and consistent, while dial scales were off by almost a kilogram at zero on average and less precise (Yorkin and colleagues, 2013). The age of the scale made no difference.

How to Read the Number: Weekly Averages

Daily weighing only works if you stop reacting to single days. Body weight normally swings by about 1 to 4 pounds over a day and by around half a kilogram from one morning to the next. Food, salt, glycogen, sweat and the menstrual cycle all move it, and it tends to peak after the weekend. Our article on how much weight fluctuates in a day measures each of those causes, so this page won't repeat them.

The fix is an average. Add up your morning weights for the week, divide by the number of mornings you weighed, and compare this week's average with last week's. A falling average means you're losing weight, however the individual mornings bounced around. Wait for the average to move in the same direction for two or three weeks before you change anything.

Here's how that looks. Say your mornings this week read 180.4, 181.6, 180.2, 179.8, 180.6, 179.4 and 179.6 pounds. The highest and lowest are 2.2 pounds apart, but the average is 180.2. If last week's average was 181.0, you're down about 0.8 pounds, even though Tuesday's 181.6 was higher than last week's average.

When Weighing Backfires

For most adults, frequent weighing doesn't harm mood or body image. A meta-analysis of 29 independent tests, covering 10,775 participants, found no link between self-weighing and anxiety or depression, body image or disordered eating, and only a small link with lower self-esteem or higher stress (Benn and colleagues, 2016). In randomized trials the associations leaned positive. They were most negative in correlational studies and, for disordered eating, in younger samples.

Daily weighing looked safe for young adults in a trial setting too. In the SNAP trial, neither daily-weighing program increased depressive symptoms or compensatory behaviors over two years. Weighing more often went with more dietary restraint, both flexible and rigid, and with better health-related quality of life (Gorin and colleagues, 2019).

Teenagers are a different story. Project EAT followed 2,516 adolescents for five years. Girls who weighed themselves often were more likely to report unhealthy weight-control behaviors and binge eating five years later, and frequent weighing didn't protect any group from weight gain (Neumark-Sztainer and colleagues, 2006). The same link didn't show up in boys.

Signs the scale is working against you

• You skip meals or add extra exercise to make up for a high reading.
• One number decides your mood for the day.
• You weigh yourself several times a day.
• You cancel plans or avoid people because of what the scale said.

If any of those sound familiar, weigh weekly or put the scale away for a while and judge progress by other measures. Our article on why you might gain weight while working out shows how to track progress with your waist, photos and training log instead. If you have a history of an eating disorder, talk with your doctor or therapist before you weigh at all.

What This Means for You

The scale is a tool for noticing, not a grade. Weigh often enough to see a trend, read the average instead of the day, and let a trend change your plan only after it has held for a few weeks.

What moves the trend is what you do between weigh-ins: training you keep showing up for and eating you can live with. Katie, who used to quit every plan after about two weeks, put it simply: "I've tried everything. This is the first time I've stuck with something past two weeks."

That's a consistency problem more than a knowledge problem, and our roundup of the best fitness apps for consistency compares the ones built to keep you coming back. FitCraft is one of them. Its 3D AI coaches demonstrate every exercise and call you by name mid-workout, and streaks, leaderboards, collectible cards and a new seasonal quest each month give you reasons to show up that have nothing to do with the scale.