The clunky first-generation Kindle employed E Ink's electronic paper technology, which is a far cry from today’s hi-res Kindle Fire HD. Interestingly, though, despite the more modern device's seemingly indelible display advantage, the e-book reader and tablet markets haven't really converged.

Amazon continues to develop e-book readers because digital book sales remain a cornerstone of the company’s business. And that goes a long way to explain the concurrent release of Amazon's Kindle Tough and fourth-generation Kindle alongside the original Fire tablet. The newest dedicated e-book reader from Amazon is called the Kindle Paperwhite, and its name does a pretty good job of describing its role.
The Paperwhite's most significant evolutionary feature is lighting. You don’t need a reading lamp over your shoulder to see this device clearly, as you might have in the past with previous e-book readers. Amazon considers this its flagship e-book reader, and the unlit models are available at even lower price points.
| Specifications | Kindle Paperwhite | Kindle | Kindle Keyboard 3G |
|---|---|---|---|
| Display Type | 6" Paperwhite | 6" E Ink Pearl | 6" E Ink Pearl |
| Dimensions | 6.7" x 4.6" x 0.36" | 6.5" x 4.5" x 0.34" | 7.5" x 4.8" x 0.34" |
| Weight | 7.8 oz (3G), 7.5 oz (Wi-Fi) | 5.98 oz. | 8.7 oz |
| User Accessible Space | 1.35 GiB | 1.35 GiB | 3.05 GiB |
| Battery | Li-ion Polymer 1470 mAh (3.7 V) | Li-ion Polymer 890 mAh (3.7 V) | Li-ion Polymer 1750 mAh (3.7 V) |
| Battery Life | 8 weeks (wireless off) | 4 weeks (wireless off) | 8 weeks (wireless off) |
| Text To Speech/MP3 Playback | No | No | Yes |
| Special Offer Price | 3G: $179 Wi-Fi: $119 | $69 | $139 |
| Regular Pricing | 3G: $199 Wi-Fi: $139 | $89 | $159 |
The generic Kindle moniker now refers to the fourth-generation model we reviewed in Hands-On: Amazon’s Fourth-Gen Kindle Refresh; the only difference is that it’s now also available in black. Yes, today, the “Kindle” is Amazon's barebones budget model, retailing for just $69. It lacks touch sensitivity, so you need to use navigation buttons to hit keys on a virtual keyboard. If that’s too much of a pain for you, Amazon still sells the Kindle Keyboard 3G, though it'll run you an additional $60 bucks.
In comparison, the Wi-Fi-equipped Kindle Paperwhite costs $139, or $119 with special offers (basically, Amazon’s ad system). If you’re constantly on the move, with less access to Wi-Fi, it might be worth paying $60 more for the 3G-equipped model, which lets you make purchases on the road without 802.11 connectivity.

Physically, the Kindle Paperwhite is slightly larger than the base Kindle e-book reader. The major difference between them is weight, though the flagship mode is only an ounce-and-a-half heavier. Compared to the Kindle Keyboard 3G, there’s no question that Amazon's Paperwhite is both smaller and lighter.

This product effectively replaces the Kindle Touch, which explains why it feels so familiar in our hands. As a touch-based e-book reader, the Paperwhite is devoid of physical I/O, aside from a power button along its bottom edge. Amazon continues to use a rubberized plastic back cover, which is texturally comfortable to grip, and unlike the aluminum and glass iPad.
Interestingly, Amazon claims that the Paperwhite boasts an astounding eight weeks of battery life. That's double what you can expect from the base-model Kindle, but seemingly plausible, given the Paperwhite's larger 1,470 mAh power source. With that said, the battery's scaling suggests that the e-book reader's light isn't a significant drain. Although it's impractical to run our usual battery life tests on the Paperwhite, a week of constant use gives us every reason to believe that you can read for a few hours a day and not have to bother reaching for a charger.
E Ink, Revisited
At its core, the Paperwhite remains an E Ink-based e-book reader. So, page refresh times are still significantly slower than what you’ll ever see on a tablet’s LCD.
E Ink employs charged microscopic capsules in order to generate images. So, the screen's refresh rate directly correlates to the time it takes to charge electrodes and move the capsules. This process isn't measured in single-digit milliseconds, as it might be on a tablet. Rather, the latency is quantified in the hundreds of milliseconds.
Paperwhite: What’s Different?
For starters, the Paperwhite employs a capacitive touch sensor, as opposed to the previous Kindle Touch's infrared sensor. This improves response times noticeably. Back in January of last year, we benchmarked screen refresh rates on the Kindle Touch and found them to be about 50-100 ms slower than the non-touch version and older Kindle Keyboard. The capacitive sensor yields a substantial speed-up; we can't detect a noticeable difference in the delay.
Perhaps more important, Amazon adds LED lights to the Paperwhite, allowing you to read the display in the dark. Backlight might be the wrong term to use, though. While tablet screens and computer monitors are illuminated by LEDs that emit light out towards the user, the Kindle Paperwhite shines light back down towards the screen. Ergo, the Paperwhite’s backlight is actually a frontlight.
The clip below is an excerpt from Amazon’s official Quick Tour video, which gives a breakdown of this technology:
In the next video, Amazon employees talk about the challenges they faced designing the Kindle Paperwhite.
It was actually very hard: We had to spend many hours in dark rooms to pick LEDs. We looked at samples and looked at for this batch here these are the best LEDS to match the characteristics of a white, very neutral color. We spent a lot of time looking at how many LEDs to put in, how hard to drive them, how bright we could get it without impacting the battery life. You don’t want someone to have to [consciously] manage their light, and say, I’d really like to have the light on but that’s gonna hurt my battery life.
In a nutshell, Amazon combined the extremely power-efficient characteristics of a non-glare display with a touch-sensitive screen, and managed to tack on illumination for good measure. This is nothing short of a tremendously impressive feat.

To be precise, the Paperwhite’s display employs a light guide that sits atop the capacitive touch sensor. The guide is made of a transparent material, and light from white LEDs enters at the bottom edge of the display, bouncing along nanoimprinted channels within the guide. Amazon says it operates in much the same way as a fiber optic cable, though the company doesn't share much more detail than that.

The nanoimprinted channels are responsible for an even distribution of light across the entire display. Because the LEDs provide the strongest illumination towards the bottom edge of the screen, the criss-cross pattern of these channels becomes denser towards the upper edge, intensifying the output to maintain even distribution of brightness throughout.
We’ve measured varying levels of contrast between different E Ink-based displays. In fact, the fourth-generation Kindle's display actually seemed worse than its predecessor's.
Deeper Blacks On Kindle Keyboard (Right)
At first, we couldn’t be sure if this was an optical illusion or an actual step backward. However, like actual paper, E Ink-based displays require reflected light to read text. So, we took a cue from our exploration of printer paper (Tom's Hardware Benchmarks Inkjet Printer Paper!), where our NIST-certified i1Pro calibration tool allowed us to measure paper's color performance. The i1Pro contains a finely-calibrated light source that illuminates a color patch with a fixed amount of light, removing our eyes as a variable.
We can apply that same methodology to e-book readers because E Ink-based displays operate on the same principle.

The benchmark process is fairly simple. Since E Ink Pearl supports 16 different shades between black and white, we're using Photoshop to create monotone backgrounds starting from #000000 (the six-digit hexadecimal number for black) and progressively increasing the hue until reaching #FFFFFF (white). The end is 16 evenly-spaced shades, from white to black. We then use our spectrophotometer's printer measurement mode to take color space readings.

The L value on the Y-axis is traditionally referred to as the "lightness of a color." This is measured on a 0-to-100 scale, where higher values indicate lighter colors. So, true black would have an L value of 0, while pure white has a value of 100.
According to our previous results, the fourth-generation Kindle suffered a slight reduction in contrast compared to previous models. Subjectively, the Kindle Paperwhite appears very close to the third-generation Kindle (known as the Kindle Keyboard), and our benchmark results largely concur, with a couple of caveats. First, solid black appears slightly darker on the Paperwhite compared to previous Kindles. Unfortunately, lighter shades also appear a tad darker on the Paperwhite.
Interestingly, Amazon's Kindle Paperwhite lets you set the contrast on a five-point scale. This is a new feature unique to the company's e-book reader flagship. By default, the Paperwhite is set to the middle point, which we’re calling “normal contrast.” Notched up to “high contrast,” you’ll see a bigger difference between pure black and true while. However, this comes at the expense of the shades in between.
That's not the end of the story, though. There's a long-running debate about the quality of E Ink screens. Specifically, is there actually a difference between Kindle generations, or are our eyes playing tricks on us? Our benchmarks prove a difference exists using hard data. But that doesn't eliminate another possibility: quality variation. To quote our fourth-generation Kindle review:
“We called up E Ink Corporation to ask if this was a batch-related issue, and was told that this is most likely due to Amazon choosing a particular grade of display panels.”
While we discussed many aspects of e-book readers in that review, that line in particular stirred up quite a lot of controversy. We want to once again say that it is possible to purchase two e-book readers of the same model and get a different experience. It’s not just in your head. E Ink uses a chip called Broadsheet to control its panels, and the following is a quote from GPL source code in the Linux broadsheetfb driver:
Broadsheet is a framebuffer device. It is slightly different from a typical framebuffer controller that drives a normal TFT-LCD display. Most E-Ink display panels require a waveform in order to function. That is, in order to drive the state of a pixel to black, gray, or white, a specific waveform is utilized. Basically, that waveform represents the specific E-field wiggling needed to get the pixel to its optimal state given current temperature, and its previous state. TN/IPS-LCDs use a similar concept but the driving waveform is sufficiently simple that it is internalized in the TFT source/gate driver.
These E-Ink waveforms are specific to a production batch. That is, a batch of display films are produced, then they get characterized and a waveform is generated for that batch. Broadsheet, typically, is attached to its private SPI flash which is then flashed with this waveform. Users won't be able to see the waveform and typically won't ever need to know about it. If however, the display panel attached to broadsheet is changed out, then they will need to update their waveform. That would typically be done at a factory or repair facility rather than by a user.
In a nutshell, once a batch of E Ink displays are manufactured, they go through quality control where a set of unknown characteristics get analyzed. This data is then used to generate a waveform for that batch. The waveform itself represents the specific electrical technique used to transition from black to white (and vice versa). While E Ink manufactures its panels to a tight spec, it’s very possible to get displays at the outer limits of what might be considered acceptable.
Does that mean our benchmarks are moot?
Yes and no. We’ve benchmarked multiple Kindles, and there still appears to be a slight difference between certain models. Fortunately, if you are having a problem, Amazon’s free return policy makes a replacement rather painless, so the possibility of getting stuck with a lemon shouldn't get in the way of your purchasing decision.
Next, let's compare the Kindle Paperwhite under various lighting conditions and brightness settings.

Regardless of whether you use it in bright sunlight or in a well-lit room, the Paperwhite looks surprisingly natural. Truly, like a piece of paper. There's no washout, and text appears crisp throughout the display.

Even when we dial it down to 66% brightness, the Paperwhite still manages to look great.

In poorly-lit environments, Amazon recommends setting the Paperwhite to a low brightness level. If you’re in complete darkness, you can even dial the brightness down to its absolute minimum and still read the screen reasonably well. The Kindle Paperwhite presents a perfect solution for those of us keeping our significant others up at night with a bedside lamp.
The Kindle Paperwhite succeeds Amazon's Kindle Touch, which also employed a touchscreen. In fact, the home screen and general interface layout of the two devices are quite similar.
As a touch-based e-book reader, the Paperwhite naturally lacks physical buttons. Instead, Amazon employs a user interface that it calls EasyReach, which relies on defined zones for menu access and turning pages.
It's easy enough to access the menu and toolbar; simply tap the top of the screen. To flip to the next page, tap the lower-right half of the screen. Likewise, tap the leftmost edge to go back to the previous page. To take a screenshot, simultaneously tap and hold any two opposite corners of the screen (for example, the top-right and bottom-left, or top-left and bottom-right).
Our only complaint is that EasyReach, in its current form, is optimized for right-handed users. Ideally, we'd like to see an alternative layout for lefties.
After you open a book, the menu is automatically hidden. Only after you tap the top edge does it reappear.

If you're not familiar with the Kindle family, models sold with ”Special Offers" do not differ in any significant way from those without. The sleep screen is the only thing that sets them apart. Instead of pictures, Special Offers models display Amazon advertisements. And they’re not just limited to books. Kindles with Special Offers push ads for anything Amazon sells that the company wants to promote, such as a coupon for $30 off a pair of $100 jeans (an actual example). If you don't mind the ads showing up when you're not using your Paperwhite, buying a Special Offers model allows you to secure a lower price.
Bibliophiles will love Amazon’s latest e-book reader. For a long while, LCD-based tablets had the a big advantage over these devices based on their bright, vibrant, screens. But the Kindle Paperwhite no longer requires ambient lighting for you to use it.

Reading e-books on a tablet was never a pleasant experience for me. The very nature of LCD technology leads to eye strain and battery life measured in hours. In comparison E Ink's technology is very efficient, enabling devices that run for weeks between charges instead. Having used the Paperwhite for several months now, I can personally comment that using Amazon's reader is no more taxing on my eyes than an actual book. If you can't put down that page-turner, you don't have to. I've never felt like I needed to take a break. The same is not true of an inexpensive tablet like the Nexus 7.
Ah, the inexpensive tablet dilemma. The Nexus 7 and Kindle Fire HD both sell for $199. The non-HD version of the Fire is now $159. Meanwhile, Amazon is asking $119 for the Special Offers version of its Paperwhite. It's really hard not to pay a little bit more for a more feature-rich tablet, isn't it?
Not only are tablets commonly used for reading e-books, but you can browse the Web, play games, take notes, listen to music, watch movies, balance your budget...the list goes on and on. You can also browse the Web on the Paperwhite, though it's impossible to get the full online experience without color. And your choice of games is limited to crossword puzzles and solitaire. And so, the decision to buy a tablet or an e-book reader comes down to what you do most. If you plan on reading books more than anything else, a reader gives you a much better experience than a tablet, and Amazon's Kindle Paperwhite approaches the bibliophile’s dream device. It's only lacking the ability to display colors, and Amazon is already working on that.
In the meantime, the Paperwhite is enough of an upgrade over past Kindles that we're awarding it our Tom's Hardware Approved Award. There's a lot to like here, though we'd like to see an even lower price to keep the e-book reader more differentiated from modern $200 tablets. But for what it's designed to do, this is definitely the Cadillac of e-book readers.






