EyeStill vs SwiftRead, Bionic Reading and Spreeder

Most speed-reading tools pick one trick: either they flash words at a fixed metronome beat, or they bold the first half of every word on a static page. Here is where each approach works, where it wears out, and what EyeStill does differently.

At a glance

1. SwiftRead (formerly Spreed) and Spreeder

SwiftRead is the best-known RSVP extension in the Chrome Web Store, and Spreeder is one of the oldest web trainers. If you select text on a webpage and open SwiftRead, it puts the passage into a clean modal and flashes one word at a time.

Where classic RSVP starts to hurt is the clock. At 350 words per minute, a standard RSVP timer gives almost every word the same 171 milliseconds. As we wrote in Speed reading 2.0, eye-tracking studies show that natural reading is never uniform: common function words (the, of, in) are recognized in a glance, while low-frequency nouns, names, and unexpected turns need extra time to integrate. When a flat box flashes past a dense word at the same speed as a preposition, you lose the thread of the sentence two words later.

How EyeStill differs:

• Adaptive timing at the same average WPM: EyeStill checks every word against 30,000-word frequency tables, scores how predictable it is after the previous word (surprisal), and runs a small neural model (RuBERT-tiny on WebGPU) in the browser to hold topic shifts and rare terms longer — then catches up on predictable words so your average speed stays what you set. You can compare both modes side by side on our speed test page.
• Spatial 3D drum: Instead of harsh on-off strobing in a flat box, upcoming words curve into view on a subtle 3D cylinder so your peripheral vision sees word length and punctuation before it reaches the red focus letter.
• No popup modal required in AI chats: In ChatGPT, Claude, Gemini, and DeepSeek, the reading line opens directly underneath the assistant's reply — even while the model is still streaming.

2. Bionic Reading

Bionic Reading bolds the first few letters of every word to create "artificial fixation points." Many readers — especially people who lose their place in long paragraphs — find that the visual contrast helps keep their attention on the page.

The limitation is physical: because the text remains a static block of lines, your eyes still have to make four to five saccadic jumps per second from left to right and sweep back to the start of each new line. There is also no pacing control when your mind starts to wander.

How EyeStill differs:

• Zero eye travel during flow, Bionic context on pause: In EyeStill Reader, you read at one fixed point with zero line jumps. Whenever you pause or press C, the full paragraph opens in Bionic typography so you can inspect the surrounding sentences at a glance.
• Attention-aware webcam pause (optional): If you turn on local webcam gaze tracking in the reader, EyeStill notices when your eyes leave the screen, pauses automatically, and rewinds two words to the start of the clause when you look back.

3. Beyond books: video subtitles and Claude

Most of what we read all day isn't an EPUB file — it is video captions and AI responses. Neither SwiftRead nor Bionic Reading touches video.

On YouTube, EyeStill tracks the active speaker's face in the browser and places subtitles one word at a time right at their lips. Instead of your eyes playing ping-pong between the bottom of the video and the speaker's face, you watch their expression and read the words (or a context-aware translation) in one spot. And if you create vertical video, EyeStill Studio exports MP4s with face-tracking captions in your browser for free, with no sign-up or cloud upload.