The Dell UltraSharp U4021QW is a great office monitor with an impressive 5k x 2k resolution and a large 40 inch screen, making it very well-suited to productivity and multitasking. It also has some nice extra features, like Picture-in-Picture/Picture-by-Picture and KVM switch capability, but lacks others like HDR support, Black Frame Insertion (BFI), and variable refresh rate (VRR). It has a low contrast ratio, typical of an IPS panel, but its viewing angles are great, so the image stays accurate when viewed from the sides. It also has an incredible color gamut. It gets decently bright, enough to overcome glare in moderate lighting conditions, but it may struggle in very bright rooms. Its response time is decent; fine for casual gaming, but probably not fast enough for more competitive gamers.
The Dell U4021QW is a good all-around monitor. The large size is well-suited to productivity or immersing yourself in a movie or game, and its exceptionally high resolution delivers a crisp image. It also has an incredible color gamut for content creators working in the sRGB color space. While its response time is fine for casual gaming, it may be too slow for serious gamers, and unfortunately, there's no VRR support.
The Dell U4021QW is a great office monitor. Its uniquely large size and resolution let you juggle multiple windows, and it comes with extra features like PIP/PBP and KVM switch. Text clarity is exceptional, and it has great viewing angles, making it easier to share content. Unfortunately, its peak brightness is only decent, so glare may be an issue in very bright, sunny rooms.
The Dell U4021QW is decent for gaming. It's limited to a 60Hz refresh rate, and while its response time is decent, it may be too slow for more serious gamers. On the upside, the input lag is low, and it has wide viewing angles. Also, its large size is perfect for immersing yourself in a game.
The Dell U4021QW is decent for multimedia. The size and resolution are incredible for watching movies or other content, delivering plenty of space and a super crisp image. Unfortunately, it has a sub-par contrast ratio, so black looks more like gray in the dark.
The Dell U4021QW is a good media creation monitor. It has an incredible color gamut, including great coverage of the Adobe RGB color space used in photo editing. The size is great for opening multiple windows, and its exceptional 5k x 2k resolution delivers a crisp image. Unfortunately, it has a low contrast ratio, so blacks look more grayish in the dark.
The Dell U4021QW doesn't support HDR.
The Dell U4021QW has a curved ultrawide screen and a similar overall design as other UltraSharp monitors. It's sleek and simple, with thin black bezels and a silver body, and it should look great whether you're working in the office or using it at home.
The Dell U4021QW has a similar trapezoidal stand as other Dell UltraSharps like the Dell U3818DW. It supports the monitor well and doesn't take up too much space.
The ergonomics are good, although it scores lower because it can't rotate into portrait mode. That's because of its ultrawide screen, though, which you likely wouldn't want to rotate anyway.
The back of the monitor is clean and simple. There's a cutout in the stand for cable management.
Because of the screen's curve, it has a somewhat thicker profile, but all things considered, it's quite thin and doesn't require a deep desk.
The Dell U4021QW feels fairly well-built. It's very heavy, and the plastic is quite rigid, and the feet grip very well, so you're unlikely to move it by accident. However, there's some flex where the panel meets the plastic backing all around the monitor that makes it feel less well put together.
The Dell U4021QW has a sub-par contrast ratio, although it's about expected for an IPS panel. Our unit is slightly lower than the advertised 1000:1, but contrast can vary between individual units.
This monitor doesn't have a local dimming feature. The video above is provided for reference only.
SDR peak brightness is decent, although it's slightly lower than the advertised 300 nits. It stays very consistent with difference scenes, though, which is great.
We measured the SDR brightness after calibration using the 'Custom Color' Picture Mode, with Brightness set to max.
The Dell U4021QW doesn't support HDR.
The Dell U4021QW has great horizontal viewing angles, which is good for sharing content and ensures the edges of the screen remain accurate when sitting up close.
Verticle viewing angles are decent, but you still lose some image accuracy when viewing from above or below.
The Dell U4021QW has excellent gray uniformity, although this can vary between units. The corners and edges are a bit darker, and there's some slight dirty screen effect, but it should be very hard to notice with actual content. In near-dark scenes, the uniformity is even better.
The Dell U4021QW scores a bit higher for black uniformity than it should. Due to its size and the screen's curve, the corners of our test photo are cropped, but as you can see here, there's noticeable backlight bleed in the corners. The whole screen looks more gray than black, and there's a bit of clouding throughout, as well as blooming around the test cross. Keep in mind that black uniformity may vary between units.
The Dell U4021QW has fantastic out-of-the-box color accuracy, but this can vary between individual units. Most colors are very accurate, and the white balance is excellent too. Gamma follows the curve fairly well, although very dark and very bright scenes are a bit over-brightened. The color temperature is close to our 6,500K target but a bit on the warm side.
After calibration, accuracy is incredible. Any inaccuracies shouldn't be noticeable to the naked eye. Gamma is improved overall, and the color temperature is close to perfect.
You can download our ICC profile calibration here. This is provided for reference only and shouldn't be used, as the calibration values vary per individual unit due to manufacturing tolerances, even for the same model.
The monitor has an exceptional SDR color gamut. It has full coverage of the sRGB color space and excellent coverage of the wider Adobe RGB used in photo editing. It's also advertised as having 98% coverage of the DCI P3 color space, but this isn't something that we test outside of HDR, which isn't supported on this monitor.
SDR color volume is superb. It can produce a wide range of bright colors. It only really struggles a bit with deep, dark colors due to its limited contrast ratio.
There are no signs of temporary image retention, but this may vary between units.
Gradient performance is incredible. You shouldn't notice any banding.
There's no noticeable color bleed on this monitor.
The Dell UltraSharp U4021QW has adequate reflection handling, but we don't recommend placing it opposite a window or direct lighting.
Text clarity is exceptional. The monitor's 5k resolution produces very clear text. Enabling ClearType (top photo) makes text look a little bolder.
|Overdrive Setting||Response Time Chart||Response Time Tables||Motion Blur Photo|
The Dell U4021QW has a decent response time at its max refresh rate. It should be fine for casual gaming but wouldn't cut it for more competitive gamers. The recommended overdrive setting is 'Normal' because it's reasonably fast and has much less overshoot than the 'Fast' setting.
The max refresh rate is 60Hz.
The Dell U4021QW has a flicker-free backlight, which can help reduce eye strain.
This monitor doesn't have a Black Frame Insertion (BFI) or backlight strobing feature.
The Dell U4021QW has a maximum refresh rate of 60Hz, which should be fine for most people using it mostly for productivity. The max refresh rate over HDMI is only 30Hz, though, so you need to use DisplayPort to get 60Hz. Unfortunately, it doesn't support VRR to reduce screen tearing in games.