Dark Mode vs. Light Mode: Which Is Better? (2023)

Recently, spurred by the introduction of dark mode in IOS 13, a reporter asked me to comment on the usability of dark mode and its popularity as a design trend. It’s a question that I also got several times from attendees to ourUX Conference.

Dark Mode vs. Light Mode: Which Is Better? (1)

I must say upfront that NN/g has not done its own research on dark mode. However, these questions prompted me to do a review of the academic literature on whether dark mode has any benefits for users — with normal vision or not. I will share these findings with you.

But first, let’s make sure we’re all on the same page by defining some vocabulary.

Definition: Contrast polarity is a term used to describe the contrast between the text and the background:

  • Positive contrast polarity (light mode) refers to dark-font text on light background.
  • Negative contrast polarity (dark mode) denotes the combination of light (e.g., white) text on dark (e.g., black) background.

Dark-mode displays emit less light than light-mode ones (and, because of that, they might extend battery life). But the amount of light in the environment influences not only power consumption, but also our perception. In order to understand how, let’s briefly review some basic information about the eye pupil and how it reacts to the amount of light in the environment.

The Human Pupil Is Sensitive to the Amount of Light

The human pupil is the gateway to the retina: through it, light reaches the eye. By default, the human pupil changes size depending on the amount of light in the environment: when there is a lot of light, it contracts and becomes narrower, and when it’s dark, it dilates to allow more light to get in. Smaller pupil sizes make the eyes less susceptible tospherical aberrations(in which the image appears unfocused) and increase the depth of field, so people don’t have to work so hard to focus on the text, which, in turn, means that their eyes are less likely to get tired. (Camera apertures work exactly in the same way: a photo taken at f/2.8 will have a narrower depth of field and thus more blurring than one taken at f/16.)

As we age, the pupil decreases in size. Too small pupil sizes mean that too little light enters the eye, which impairs our ability to read or detect text, especially in low ambient light (for example, at night). On the other side, as we get older, we become more susceptible to glare, and glare is particularly likely under bright light.

Normal-Vision Users

Early studies conducted in the 1980s seemed to point out that, for people with normal vision or corrected-to-normal vision (i.e., wearing appropriately prescribed glasses or contacts), the contrast polarity did not affect visual performance.

Yet, several more recent studies contradict that initial finding. In particular, we will focus on two articles that involved two different types of tasks: one, published in 2013 in the journalErgonomics,looked at visual acuity and reading performance, and the other one, published in 2017 inApplied Ergonomics, investigated performance for aglanceable-readingtask — the quick reading of 1–2 words that people often engage in when they interact with a mobile phone, asmartwatch, or a car dashboard and that is involved in activities such as checking directions or attending to a notification.

(Video) Dark Mode vs. Light Mode Battery Test

Effects of Contrast Polarity on Visual Acuity and Proofreading

Cosima Piepenbrock and hercolleagues at the Institut für Experimentelle Psychologie in Düsseldorf, Germany studied two groups of adults with normal (or corrected-to-normal) vision: young adults (18 to 33 years old) and older adults (60 to 85 years old).None of the participants suffered from any eye diseases (e.g., cataract).

The participants were given two different types of tasks:

  • A visual-acuity task, which involved detecting the gap in aLandolt C optotype— in other words, showing them asymbol similar to the letter “C” oriented in various way and asking them to identify where the gap is (e.g., top, bottom).
  • A proofreading task, which involved reading a short passage and identifying different types of errors

The tasks were presented in different contrast polarities — for some participants, they were in dark mode and for others they were shown in light mode. Contrast polarity was abetween-subjectsvariable, meaning that each participant saw only tasks in one contrast polarity (e.g., only dark mode).

The researchers also collected pre- and post-test fatigue-related measures: participants rated their eyestrain, headache, muscle strain, back pain, and subjective well-being at the beginning of the experiment, as well as at the end.

Their results showed that light mode won across all dimensions: irrespective of age, the positive contrast polarity was better for both visual-acuity tasks and for proofreading tasks. However, the difference between light mode and dark mode in the visual-acuity task was smaller for older adults than for younger adults — meaning that,although light mode was better for older adults, too, they did not benefit from it as much as younger adults, at least in the visual-acuity task.

When researchers looked at fatigue metrics, they concluded that there was no significant difference of contrast polarity on any of them (meaning that it wasn’t the case that dark mode made people more tired, or vice versa).

Another study, published in the journalHuman Factorsby the same research group, looked at how text size interacts with contrast polarity in a proofreading task. It found that the positive-polarity advantage increased linearly as the font size was decreased:namely, the smaller the font, the better it is for users to see the text in light mode.Interestingly, even though their performance was better in the light mode,participants in the study did not report any difference in their perception of text readability(e.g., their ability to focus on text) in light versus dark mode — which only reinforcesthe first rule of usability: don’t listen to users.

Effects on Contrast Polarity on Glanceable Reading

Jonathan Dobres and his colleagues at MIT’s Agelab attempted to quantify whether ambient lighting conditions (simulated daytime compared to simulated nighttime) affect in any way the advantage of positive polarity in the context of a lexical-decision task. A lexical-decision task, a paradigm commonly used in psychology, involves showing participants a string of letters and having them decide whether it’s a word or a nonword.A lexical-decision task is more similar with the glanceable reading that we do in highly interruptible conditions such as when driving or using a mobile phone or smartwatch on the go — all of these involve quickly looking at a display and extracting the relevant information.

(Video) Is Dark Mode Actually Better For Your Eyes? - Cheddar Explains

The participants in the Agelab study had normal or corrected-to-normal vision. They were shown character strings at two possible contrast polarities (dark mode vs. light mode), in different ambient lights (daytime vs. nighttime), and at different font sizes.

The study found that lighting, polarity, and text size all had an effect on performance — in the direction perhaps expected by now: simulated daytime lead to faster judgements than simulated nighttime, light mode was better than dark mode, and bigger font was faster than smaller font. The interesting result was the significant interaction between ambient lighting and contrast polarity:during daytime, there was no significant effect of contrast polarity, but during nighttime, light mode led to better performance than dark mode.Moreover, during nighttime it was much harder for people to read small-font text in dark mode than in light mode.

Dark Mode vs. Light Mode: Which Is Better? (2)

The lack of effect of polarity in simulated daytime environments was somewhat surprising and inconsistent with a different older study by Buchner and Baumgartner, that also looked at bright vs dark ambient conditions. However, in that study the bright ambient light was much lower than the one used in the Agelab study (think office light versus bright outdoors light). Dobres and his colleagues argue that the amount of ambient light may affect the positive-polarity advantage, with bright light leading to zero difference, but normal office light still being able to produce a difference.

Long-Term Effects

The literature reviewed so far looks at one-time effects of contrast polarity on human performance. But how about long-term effects? In other words, does long-term exposure to one type of contrast polarity have any effects?

An intriguing study published in Nature Research’s Scientific Reports in 2018 suggests that sustained exposure to light-mode may be associated with myopia. Myopia (or nearsightedness) refers to the inability to see far objects clearly and is strongly correlated with the level of education and with reading. In their study, Andrea Aleman and her colleagues at University of Tübingen in Germany asked 7 human participants to read text presented in dark mode and light mode for an hour each. To see if their predisposition to myopia changed after reading, they measured the thickness of the choroid, a vascular membrane behind the retina. The thinning of the choroid is associated with myopia.

The researchers found significant thinning of this membrane when participants read text presented in light mode and significant thickening when reading text presented in dark mode. The thinning was more pronounced in participants who already had myopia.

This result seems to suggest that, even though performance in light mode may be better in the short term, there may be a long-term cost associated with it.

Users with Impaired Vision

The literature on users with impaired vision, is paradoxically, less rich than the one on people with normal vision, although there is an implicit consensus that dark mode is better at least for some people with visual impairments.Gordon Legge and his colleagues at University of Minnesota define two low-vision categories: (1) due to central-vision impairments and (2) due to cloudy ocular media.

(Video) 'Dark Mode' Is Not What You Think...

The ocular media refers to the various transparent substances in the eye, including the cornea and the lens. The most common cause of cloudy ocular media is cataract, which refers to the clouding of the lens and is fairly common in older people. A cataract scatters and blocks some of the light that is supposed to reach the retina through the lens and thus prevents the creation of a clear, focused image on your retina.

Even as early as 1977, a study by Sloan reported that some people with low vision prefer dark mode. (Inour own accessibility studies, Kara Pernice has also seen users with low vision sometimes switching between dark and light mode in an attempt to gain clarity.) In 1985, Gordon Legge and his colleagues at University of Minnesota hypothesized that this effect is due to “abnormal light scatter due cloudy ocular media” — presumably, because, if more light reaches the eye with a cloudy lens, there’s a bigger chance of a distortion. Thus, dark mode may be better for people with cloudy ocular media because the display emits less light.

In Legge’s study, each of the 7participants with cloudy ocular media had better reading rates with dark modes, whereas the rest of the participants, who had impaired central vision, were not affected by contrast polarity.

Legge’s studies formed the basis of recommending the possibility of switching to dark mode for modern computer interfaces. In 2005, Papadopoulos and Goudiras, in an article that reviewed various accessibility best practices for low-vision users, recommended the availability of dark mode in user interfaces.

A caveat noted by several of the researchers in the normal-vision field is that Legge’s studies with low-vision users were conducted with CRT displays, as opposed to the LEDs used in most modern displays. These displays were more susceptible to flicker in light mode than in dark mode, thus possibly biasing the results against the light mode.


So, should you jump on the dark-mode bandwagon?While dark mode may present some advantages for some low-vision users — in particular, those with cloudy ocular media such as cataract, the research evidence points in the direction of an advantage of positive polarity for normal-vision users. In other words,in users with normal vision, light mode leads to better performance most of the time.

Why is light mode better for performance? These findings are best explained by the fact that, with positive contrast polarity, there is more overall light and so the pupil contracts more. As a result, there are fewer spherical aberrations, greater depth of field, and overall better ability to focus on details without tiring the eyes.

Even though larger font sizes and bright ambient light may erase some of this advantage in people with normal vision, at this point we don’t recommend switching to dark mode by default if your target audience includes the general population.

(Video) Why is EVERYONE Switching to DARK MODE?

That being said, we strongly recommend thatdesigners allow users to switch to dark mode if they want to— for three reasons: (1)there may be long-term effects associated with light mode; (2) some people with visual impairments will do better with dark mode; and (3) some users simply like dark mode better. (We know that peoplerarely change defaults, but they should be able to.) It’s unlikely that people will alter the display mode for any random website, but, if a website or an application sees frequent use, it should consider providing this option to its users. In particular,applications meant for long-form reading (such as book readers, magazines, and even news sites) should offer a dark-mode feature. And the option should ideally be pervasive throughout all the screens of that website or application. Moreover, if an operating system provides a dark-mode API (like iOS does), make sure you take advantage of it — doing so will give those users who decide to switch to dark mode the ability to experience your application or website in their chosen contrast polarity.


A. Aleman, M. Wang, and F. Schaeffel (2018). Reading and Myopia: Contrast Polarity Matters.Scientific Reports8, 10840 (2018) doi:10.1038/s41598-018-28904-x

J. Dobres, N. Chahine, B. Reimer (2017). Effects of ambient illumination, contrast polarity, and letter size on text legibility under glance-like reading,Applied Ergonomics.DOI: 10.1016/j.apergo.2016.11.001

G.E. Legge, G. S. Rubin, D. G. Pelli, and M. M. Schleske (1985). Psychophysics of Reading – ii. Low Vision.Vision Research.

K.S. Papadopoulos., D. B. Goudiras (2005). Accessibility Assistance for Visually-Impaired People in Digital Texts.British Journal of Visual Impairment.DOI: 10.1177/0264619605054779.

C. Piepenbrock, S. Mayr, I. Mund & A. Buchner (2013). Positive display polarity is advantageous for both younger and older adults,Ergonomics, DOI:10.1080/00140139.2013.790485

Cosima Piepenbrock,S. Mayr,A. Buchner(2013). Positive Display Polarity Is Particularly Advantageous for Small Character Sizes: Implications for Display Design.Human Factors.DOI: 10.1177/0018720813515509

L.L. Sloan (1977). Reading Aids for the Partially Sighted: A Systematic Classification and Procedure for Prescribing. Baltimore, MD: Williams & Wilkins.

(Video) Dark Mode vs Light


Which is better dark or light mode? ›

Some experts say it's easier and healthier to read text against a dark background as it reduces eye strain, while other studies arrive at the opposite conclusion. There's also a debate about whether dark mode can make your smartphone battery last longer. Many mobile users simply think dark mode looks more slick.

Is it better to use dark mode? ›

Is dark mode better for your eyes? While dark mode has a lot of benefits, it may not be better for your eyes. Using dark mode is helpful in that it's easier on the eyes than a stark, bright white screen. However, using a dark screen requires your pupils to dilate which can make it harder to focus on the screen.

Which mode is good for eyes? ›

Dark mode is intended to reduce blue light exposure and help with eye strain that comes with prolonged screen time.

Which is best mode for mobile dark or light? ›

Why you should use dark mode. The most commonly known and scientific advantage of the dark mode is that it saves energy consumption on devices with OLED or AMOLED displays.

Is dark mode healthy for eyes? ›

Conversely, in a brightly lit environment, a darker screen can actually force your eyes to work harder. If truly concerned about eye strain or dryness, you might be better off investing in artificial tears or a matte screen for your device.

Why do people prefer dark mode? ›

Reduces eye strain at night and cuts glare

Dark mode users find reading easier in low light with less eye strain. They also claim it helps them fall asleep quickly and stay asleep longer. This could be because screens expose you to more blue light at night, which could disrupt your circadian rhythm.

Who benefits from dark mode? ›

Dark mode gives designers more opportunities to explore design options for their products. A white screen can make it difficult to view certain colors. Light blue, for example, may force you to concentrate on text much carefully against a light background than a dark one.

Is light theme better for eyes? ›

Summary: In people with normal vision (or corrected-to-normal vision), visual performance tends to be better with light mode, whereas some people with cataract and related disorders may perform better with dark mode. On the flip side, long-term reading in light mode may be associated with myopia.

Why do people use light mode? ›

According to research from Cosima Piepenbrock and S. Mayr, A. Buchner in 2013, they explain that using a light-themed interface in the daytime is easier on the eyes of normal-vision people (20–20 vision or wearing prescribed glasses/contacts,) at least in the short-term.

Which screen color is best for eyes? ›

When it comes to color combinations, your eyes prefer black text on a white or slightly yellow background. Other dark-on-light combinations work fine for most people. Avoid low contrast text/background color schemes. If you wear contacts, your eyes have to work harder when staring at a screen.

Which mode is best for phone? ›

Black text on a white background is best since the colour properties and light are best suited for the human eye …

Is it OK to use phone in dark? ›

New research is detailing how blue light, which emits from smartphone and laptop screens, can damage your retinal cells, and possibly lead to macular degeneration, an eye disease that causes vision loss.

Is dark mode save battery? ›

However, if your phone's always at 100% brightness, the dark mode will save you around 39% to 47% of your battery.

Does dark mode make you tired? ›

Dark mode has been touted as a way to reduce exposure to blue light while using electronic devices, and in turn, potentially promote better sleep and minimize eye strain. "With Apple phones, for example, there's a 'night shift mode' that shifts the display to warmer colors at night," Dr.

What are the disadvantages of dark mode? ›

System-wide dark mode doesn't work with all mobile phone apps. Only certain apps are supported.

Do most people use light or dark mode? ›

According to data, 81.9% of people of smartphone users use dark mode. Another 82.7% of survey respondents claim to use dark mode with the OS. More data shows that 64.6% of people expect websites to apply dark mode automatically.

Is dark mode safer? ›

Dark mode describes an interface setting that applies a dark-colored canvas as a background. Text and objects are white or light in color. Such mode is believed to be more safe for your eyes when working at night or just in low-light environments. Additionally, it would save phone battery life.

What percentage of users use dark mode? ›

Users want to opt for Dark Mode in applications

Thus, a total of 91.8% of respondents use some form of Dark Mode on their devices.

Why does night mode hurt my eyes? ›

While dark mode does lessen the screen's overall brightness, which may seem easier on your eyes, it also causes your eyes to dilate. Since there is less light to take in, your eyes have to work harder to see clearly. Eye dilation can reduce your vision's sharpness, so you may have to strain to see well.

What color is healthiest for eyes? ›

Yellow light is the best contrast against blue light and can protect the retinas of the eyes.

Which Colour is good for brain? ›

1) Green: Concentration

Low wavelength colors promote restfulness and calm, and they improve efficiency and focus. So that's why green is an excellent color for improving concentration. Apart from being one of the easiest colors on the eyes, it reminds us of nature.

What color is easiest on eyes? ›

These colours (yellow, green, orange) are in the middle of the visible spectrum (the range of colours that our eyes can detect) and are the easiest for the eye to see. Our eyes are not as receptive or sensitive to the colours at the extreme ends of the visible spectrum (e.g., blue, violet/purple, and red).

What color is hardest on the eyes? ›

Blue is the hardest color to see as more light energy is required for a full response from blue-violet cones, compared to green or red.

Should you use dark mode during the day? ›

One of the advantages of using dark mode on your devices is that it reduces blue light exposure. Blue light is light with blue wavelengths, which promotes alertness. This can be good during the day, but blue light conversely can inhibit the body's production of melatonin, impeding the ability to sleep at night.

What is the perfect brightness for phone? ›

If your vision is better than typical, you can reduce the brightness to a lower level and save battery time. Which is the ideal brightness level for a smartphone which doesn't cause eye harm? Anything around 600 nits is good enough, but there are smartphones that push the brightness to over 1000 nits.

Is it OK to use night mode during the day? ›

The functional goal night mode is the same as dark mode, to reduce the strain on the eyes. However, unlike dark mode, which can be used throughout the day, night mode is recommended to be used during the evening, just hours before you're preparing to go to sleep.

Does phone light affect eyes? ›

Blue Light from Your Phone May Be Permanently Damaging Your Eyes. Too much screen time can wreck your eyes. Smart phones, laptops, and other handheld devices all transmit light. However, the blue light in particular may be toxic for your eyes.

How many hours should I use my phone? ›

Experts say adults should limit screen time outside of work to less than two hours per day. Any time beyond that which you would typically spend on screens should instead be spent participating in physical activity.

What's draining my battery so fast? ›

Here are some of the most common ones: There are too many push notifications and alerts draining the battery. There are too many apps running location services. There are too many apps running in the background.

Why does my battery drain so fast? ›

Your battery drains much faster when it's hot, even when not in use. This kind of drain can damage your battery. You don't need to teach your phone the battery's capacity by going from full charge to zero, or zero to full. We recommend you occasionally drain your battery to under 10% and then charge it fully overnight.

Is warm mode good for eyes? ›

Warm screen colors are easier on your eyes when you use your Mac at night or in low-light conditions. Also, exposure to bright blue light in the evening can make it harder to fall asleep.

Is day or night mode better for your eyes? ›

The night mode is known for reducing eye strain to some extent. However, there are no scientific proofs for that. Instead, text and objects can appear blurry on a dark background for some users. This makes reading difficult and increases eye fatigue.

Is yellow mode good for eyes? ›

Yellow screen is better for eyes

The yellow screen can effectively reduce the blue light emitted by the screen, relieve eye fatigue, and even help you fall asleep better at night.

Which light is harmful for eyes? ›

Ultraviolet light has the shortest wavelength and is known to be dangerous. It can burn your skin in the form of a sunburn and lead to cancer. Ultraviolet rays also can burn your eyes particularly the cornea – and lead to eye diseases such as snow blindness or welders cornea.

What color is easiest on the eyes? ›

These colours (yellow, green, orange) are in the middle of the visible spectrum (the range of colours that our eyes can detect) and are the easiest for the eye to see. Our eyes are not as receptive or sensitive to the colours at the extreme ends of the visible spectrum (e.g., blue, violet/purple, and red).

Is dark mode save battery? ›

However, if your phone's always at 100% brightness, the dark mode will save you around 39% to 47% of your battery.

Is it healthy to use your phone in the dark? ›

Using phones and tablets in the dark can speed up blindness. Blue light from your smartphones and laptops can accelerate blindness, according to a new study.

Is dark mode consume more battery? ›

Surprisingly enough, findings from the study reveal that dark mode is unlikely to impact the battery life of a smartphone significantly. Though it does use less battery than a regular light-coloured theme, the difference is unlikely to be noticeable “with the way that most people use their phones on a daily basis.

What color is safest on the eyes? ›

Yellow light, has been proven effective in protecting the retinas of patients exposed to excessive blue light, since it offers the best contrast.


1. Is Dark Mode Better For You?
2. The Real Reason You Should Be Using Dark Mode
3. Why dark mode isn't always better for eyesight
(Vulcan Post Malaysia)
4. Is light or dark mode better for eyes?
(Ask About APPS)
5. iPhone 12 (OLED) vs. iPhone 11 (LCD) Dark Mode Battery Test
6. iOS 13 REVIEW: Dark Mode VS Light Mode - Whats the Difference?
(Paul Taligato)
Top Articles
Latest Posts
Article information

Author: Jeremiah Abshire

Last Updated: 11/14/2022

Views: 5358

Rating: 4.3 / 5 (74 voted)

Reviews: 89% of readers found this page helpful

Author information

Name: Jeremiah Abshire

Birthday: 1993-09-14

Address: Apt. 425 92748 Jannie Centers, Port Nikitaville, VT 82110

Phone: +8096210939894

Job: Lead Healthcare Manager

Hobby: Watching movies, Watching movies, Knapping, LARPing, Coffee roasting, Lacemaking, Gaming

Introduction: My name is Jeremiah Abshire, I am a outstanding, kind, clever, hilarious, curious, hilarious, outstanding person who loves writing and wants to share my knowledge and understanding with you.