Readwise sends you five highlights from your Kindle library every morning at 9 AM, whether you're ready for them or not.
I've been building SmartRecall for eight months now, and the most common question I get is: "How is this different from Readwise?" Fair question — both tools promise to help you remember what you read. But after using Readwise daily for three weeks alongside my own tool, I realized they're solving fundamentally different problems.
TL;DR: Readwise is a passive highlight viewer with a great reading app bundled in. SmartRecall is an active learning system built on spaced repetition algorithms. If you want to casually resurface old highlights, Readwise ($7.99/mo) is perfect. If you need to actually memorize material — for exams, certifications, or professional knowledge — SmartRecall ($8/mo) will get you there faster.
How I evaluated them
I tested both tools with the same goal: retain key concepts from three technical books I was reading (on system design, Rust, and behavioral psychology). Here's what I measured:
- Retention mechanism — Does it use proven spaced repetition, or just random resurfacing?
- Input flexibility — How easy is it to get content into the system?
- Review experience — What does the daily workflow actually feel like?
- Effort required — How much work do I have to do to make it useful?
- Pricing & value — What am I actually paying for?
I used Readwise for my Kindle highlights and SmartRecall for manually created flashcards from the same books. Both got 20 minutes of my attention every morning.
1. Retention mechanism: Algorithms vs. randomness
Readwise doesn't use spaced repetition. It shows you a random selection of highlights each day, weighted slightly toward recent additions. You can mark highlights as "favorite" or "discard," but there's no scheduling algorithm adjusting intervals based on how well you remember something. It's essentially a shuffle button for your highlight library.
SmartRecall uses FSRS (Free Spaced Repetition Scheduler), the same algorithm that powers Anki 23.10+. Cards appear based on predicted memory decay — if you mark something "hard," you'll see it again tomorrow. If you mark it "easy," it might not come back for two weeks. The system adapts to your actual performance.
After three weeks, I tested myself on 30 concepts from my reading. For Readwise highlights I'd seen 3-5 times, I could recall about 40% unprompted. For SmartRecall cards I'd reviewed on the same schedule, I hit 78%. The difference is the algorithm — random exposure doesn't create durable memory.
Winner: SmartRecall, if retention is your goal. Readwise is better if you just want to stay loosely connected to your reading without the pressure of "learning."
If you're comparing algorithms, how SM-2 compares to FSRS explains the core trade-offs.
2. Input flexibility: Frictionless imports vs. manual curation
Readwise is unbeatable here. Connect your Kindle, Instapaper, Pocket, or Twitter account, and every highlight you've ever made syncs automatically. I had 847 highlights imported in under two minutes. The Readwise Reader app (included in the subscription) also lets you highlight articles, PDFs, and newsletters directly, and those sync too.
SmartRecall requires you to create flashcards manually or import from Anki/CSV. There's no automatic highlight sync from reading apps. I spent about 90 minutes over three weeks turning my reading notes into ~120 flashcards. That's real work.
Here's the honest critique of my own tool: SmartRecall's input friction is a feature and a bug. The act of writing a flashcard forces you to process the material, which improves encoding. But it also means you won't use it for casual reading — only for stuff you're serious about learning. Readwise, by contrast, captures everything effortlessly, but that ease means you never engage deeply with the material.
Winner: Readwise for breadth and convenience. SmartRecall for depth and intentionality.
3. Review experience: Email digest vs. focused sessions
Readwise sends a daily email with 5-15 highlights. You can also review in their web app or mobile app, but the email is the core experience. It's pleasant — nicely formatted, easy to skim. You can tap "favorite" or "archive" on each highlight. Takes 2-3 minutes. Then you close the email and move on.
The problem: I found myself skimming without really thinking. Highlights would show up, I'd think "oh yeah, I remember that," and scroll past. No retrieval practice, no effort. It felt like scrolling Instagram for book quotes.
SmartRecall forces active recall. You see the front of a card (a question or prompt), try to answer it in your head, then flip to check. You rate your confidence (Again, Hard, Good, Easy), and the algorithm schedules the next review. Sessions take 10-15 minutes for 20-30 cards. It's harder work, but that difficulty is what builds memory.
I also tested Readwise's "Mastery" feature (in beta), which turns highlights into cloze deletions for active recall. It's a step in the right direction, but the scheduling is still random, and you can't customize the card format.
Winner: SmartRecall for learning. Readwise for low-effort inspiration.
4. Effort required: Set-it-and-forget-it vs. deliberate practice
Readwise is almost zero effort after setup. Highlights sync automatically, the email arrives daily, you skim for a few minutes. If you never open the app again, you'll still get value. It's designed for passive consumption.
SmartRecall demands intentionality. You have to:
- Decide what's worth turning into a flashcard
- Write clear, atomic questions
- Review consistently (the algorithm only works if you show up)
- Adjust card difficulty as you learn
This is the second honest critique: SmartRecall punishes inconsistency. If you skip reviews for a week, you'll come back to a pile of overdue cards, and the catch-up session will feel overwhelming. Readwise doesn't care if you ignore it — the email keeps coming, no guilt.
But here's the thing: learning requires effort. Readwise optimizes for feeling productive without actually changing your brain. SmartRecall optimizes for retention, which means embracing the difficulty.
Winner: Readwise if you want something effortless. SmartRecall if you're willing to do the work.
5. Pricing & value: What you're actually paying for
Readwise: $7.99/month (or $89.99/year). Includes:
- Unlimited highlight syncing from 30+ sources
- Daily review emails
- Readwise Reader (a genuinely excellent read-later app with highlighting, TTS, and RSS)
- Mastery feature (beta)
SmartRecall: $8/month (or $80/year). Includes:
- Unlimited flashcards with FSRS scheduling
- AI-assisted card generation (GPT-4 powered)
- Mobile and web apps with offline sync
- Anki import/export
- Spaced repetition analytics
Readwise is really selling you Reader + a highlight viewer. If you need a read-later app and want your highlights resurfaced occasionally, it's a great deal. The highlight review is almost a bonus feature.
SmartRecall is a pure learning tool. No reading app, no automatic imports, no frills. You're paying for the algorithm and the discipline structure. If you don't care about retention metrics or spaced repetition, you won't get your money's worth.
Winner: Depends on your use case. Readwise is better value if you want an all-in-one reading system. SmartRecall is better value if you're studying for something specific.
Who should use which tool?
Use Readwise if you:
- Want to stay connected to your reading without structured study
- Love the idea of rediscovering old highlights
- Need a read-later app and want highlight review as a bonus
- Prefer passive, low-effort daily habits
- Read widely but don't need to memorize specifics
Use SmartRecall if you:
- Are studying for exams, certifications, or professional development
- Want to actually remember technical material, not just feel inspired by it
- Are willing to invest time in creating good flashcards
- Trust spaced repetition algorithms (or have used Anki before)
- Need retention metrics to track your progress
Use both if you:
- Want Readwise for casual reading and SmartRecall for serious study material
- Have the budget ($16/mo combined) and the discipline to maintain two review habits
I'm in the "use both" camp. Readwise handles my recreational reading and article highlights. SmartRecall handles anything I need to actually know six months from now — technical concepts, frameworks, research findings.
Final verdict
Readwise and SmartRecall aren't really competitors. They're different tools for different goals.
Readwise is a highlight management system with a beautiful reading app attached. It's perfect for people who want to feel more connected to their reading without the pressure of "learning." The daily email is a gentle nudge, not a commitment.
SmartRecall is a memory system. It's for people who need to pass tests, build expertise, or retain knowledge for professional use. The algorithm works, but only if you're willing to show up consistently and do the hard work of active recall.
If you're choosing between them, ask yourself: Do I want to be reminded of what I read, or do I need to remember it? The first is Readwise. The second is SmartRecall.
And if you're serious about both — casual reading and deliberate learning — there's no reason you can't use both. Just don't expect Readwise to prepare you for an exam, and don't expect SmartRecall to make your morning coffee routine feel cozy.
