$3,000 LTD sales, $24 MRR, 600+ registered users after 6 months building KTool on the side. This is my story

Long time lurker, first time poster here 😅

Hello Indie Hackers, I'm Daniel and I've been building ktool.io on the side for 6 months. I just reached $3,000 LTD sales and currently at a modest $24 MRR. Here is everything I learned building and growing KTool.

I'll try to answer the questions that I often get asked

  1. What is your product?
  2. How did you come up with the idea? How did you validate it?
  3. What is your tech stack?
  4. How did you find your first customers?
  5. How are you finding your customers today?
  6. How did you come up with your price?
  7. What you've learned the most?
  8. What was your biggest mistake?

1. What is your product?

KTool is a browser extension that allow you to quickly send web articles, Twitter threads and newsletters to your Kindle.

UPDATE: you can send an Indie Hacker post to your Kindle. It looks something like this :D

Indie Hacker post on Kindle

2. How did you come up with the idea? How did you validate it?

I didn't. Amazon supports this functionality for years but it recently stopped the development. Many users were frustrated and I was among them.

I saw the opportunity and decided to build a better version of it.

My first idea was to send non-DRM ebooks, not just web articles. To "validate" it, I talked to people on Reddit and Twitter. Some people found it useful and so I started building it in public.

I shared my thought here :


Key takeaway: Validation is important. Even if you're building a product that is already on the market, do talk to potential customers to learn why would they use your product.

3. What is your tech stack?

I use NextJS + TailwindCSS on the front-end and FeathersJS + PostgreSQL on the back-end.

Infrastructure wise: I use Cloudflare Pages for front-end, Heroku for API servers, Render for PostgreSQL hosting & SendGrid for email handling.

The web extension is a mix of TailwindCSS, Typescript and Swift. It was a fork of this boilerplate.

This stack is not sexy or whatever, but I've been working with these exact stack for 5 years. I even developed a custom auth solution on top of FeathersJS auth. Would be much faster for me to reuse the code.

Key takeaway: Use the stack you're most familiar with. It's fine to build a side project to learn new tech. But in my experience, learning new techs while building a side business usually increase your time-to-market.

4. How did you find your first customers?

By building in public on Twitter.

I posted my crappy MVP on Twitter and got some initial positive feedback.

I keep improving the product until one day I got super lucky. Someone mentioned KTool on Hacker News:

KTool on Hacker News

And I got a couple of sales that day, completely from strangers on the Internet :D

Fun fact: I haven't implemented payment integration when the tweet went viral. It showed the doge instead. People find it hilarious.

I literally spend 1 hour live-coding :D

Key takeaway: Be consistent and don't stop tweeting about your product. With a little bit of luck, your first customers will come.

5. How are you finding your customers today?

I continue to build in public on Twitter. I'm super lucky as I got a lot of support from Twitter. KTool was mentioned by some big accounts: Tony Dinh, Simon Hoiberg, Dagobert and Arvid Kahl (guys, thanks for your supports 🙌)

I've been doing more experiments on Twitter like posting memes every week, actively promoting KTool on big accounts' threads.

In my experience, memes are fun but not a good strategy to grow your Twitter account. I do it mostly for fun.

Promoting KTool on big accounts works great though. I even got a sales 10 minutes after posting one such self-promote tweet.

Twitter was my main acquisition channel but recently, word of mouth is taking over. I'm happy that I don't have to spend too much time on Twitter like before.

I started to invest more time on SEO, Reddit & maybe Indie Hackers this month 😅

Key takeaway: try to nail one channel before jumping to another. By focusing on Twitter, I got social proof built-in. People see my build in public journey and it builds trust. Also, don't afraid of self-promoting your product

6. How did you come up with your price?

This is where I'm still struggling. I'm going to do a lot more experiments to test.

First, I set a number that I feel fair for me as a founder ($49 lifetime deal, for super early adopters).

Then I research other products and learned that a B2C product like KTool usually priced at $29-$99 per year.

I increased the price to $89. Then sales were flatlining. I did a survey to learn customers' Willingness to Pay.

And I found that at $8.9/mo it's becoming too expensive. $4.9/mo is OK. I ended up with the price $69 LTD and $49 per year.

I write a thread about the experiment here

KTool pricing experiment

Key takeaway: Pricing is hard. Don't afraid of testing it constantly.

7. What you've learned the most?

This is my first time building in public on Twitter. Learned a lot about building a good Twitter presence, what is build in public and how to do it effectively.

I got the exposure I never could imagine. Over the last 3 months, my tweets earned about 2.7M impressions :D

2.7M impressions on Twitter

If you're just started on Twitter, definitely follow Arvid Kahl and Kevon Cheung!

Key takeaway: Twitter is wonderful if you know how to do it right. Also having a supportive community is super important. I'm grateful to receive so many support from the community 🙏

8. What was your biggest mistake?

Not spending more time finding a good name. I learned a little late that KTool was associated with a scammer. I plan to rebrand KTool soon :D

KTool name

Also I should've charged earlier. The doge dialog experiment was fun though!

Key takeaway: you will make mistakes. Learn from it and improve in the future. I was disappointed at this for a while and it wasn't good.

This is my first time posting on Indie Hackers and I hope you find these learnings useful.

If you have any questions, feel free to leave it below. I'll try my best to answer ❤️

  1. 4

    Thank you for sharing this story and your lesson.
    One suggestion is you need a viral machine in your app.
    One example is in your free tier they have 5 articles per month but you can ask them share it on social media then it will be free and not count, the message can be:
    " I just send this article to my kindle to read later: "Title of article" - thank @ktool.io"

    BTW I just follow you.

    One More Thing is I ofter watch youtube and one my favour Youtube Ali Abdaal. He like to read on kindle and highlight in there. https://www.youtube.com/watch?v=eENUPfSvuuE&ab_channel=AliAbdaal . He is also active on Twitter so maybe you can email , twitter him to use your app. I think he will like it.

    1. 2

      Woah this is a GREAT suggestion. Thank you a lot Steve.

      1. 2

        ali abdaal is kind of a big deal in the productivity sector on youtube. This suggestion by SteveP, good good.

  2. 3

    That was a fantastic journey, Daniel. I've been following you on twitter. And love how Ktool has evolved over the months 😄

    1. 2

      Thank you Goutham. So glad we could help each other on this journey

  3. 3

    Thanks a lot for sharing, I loved the post, Daniel!

    I also enjoy your tweets a lot 😀

    When you say "Promoting KTool on big accounts works great though. I even got a sales 10 minutes after posting one such self-promote tweet."

    What do you mean? Can you paste a tweet example?

    1. 2

      Here are some of those tweets:


      The last one was the one got me a sale.

      To my surprise, most of the big accounts were very supportive on these tweets. The one on Sahil Bloom thread received about 10k impressions, drove a decent traffic to my site.

      Sahil even replied.

  4. 3

    amazing! we need more stories like this here!:)

    1. 1

      Glad you found it helpful, Nik :-)

  5. 2

    Should check is “Sendle” or something along that line is available… cool stuff tho!

  6. 2

    Great work, Daniel!!

  7. 2

    Great tool. Just signed up!

    Now I have various reading to look forward to at the end of each day.

    1. 2

      One thought during the sign up process:

      When landing on the 'Enter your kindle email address page' I found myself having to leave your site to google how to find my kindle email. This cost me a couple minutes and I almost considered dropping off.

      It would be nice if you provided a direct link to my Amazon account settings devices tab and/or instructions to locate that kindle email address.

      1. 2

        Thanks for your feedback. You’re right. My onboarding flow is basically non-existent. I’m in the middle of developing the onboarding flow.

  8. 2

    Dude that's a great post 🔥 So I believe you currently have 5 subbed customers. What do you think will have the greatest impact to get the next 25?

    1. 3

      Thanks Max.

      I think to get the next 25 subs, I need a better offer. Currently KTool does a great job at sending web articles, but it hasn’t worked properly with RSS and newsletters yet.

      Also, I need to execute my marketing plan, where I’d try to partner with newsletter authors.

      Their audience get to read the newsletter on their Kindle for free. They get a better “read rate” I guess. Gotta figure this out :D

      1. 2

        Do you mean that every new issue of a newsletter I've subscribed to will be automatically sent to my kindle?

        That would be pretty cool!

        1. 1

          Yes. Exactly that. I’ve got the MVP working. If you’re interested, I can grant you beta access 😁

          1. 1

            I'd love to help Daniel, but I'm one of those weirdos with a Kobo 😥

      2. 2

        As a writer myself I love the ideia :)

        Substack is a great start

      3. 2

        I love the marketing strategy with the newsletter  👌 Looking forward to see your execute on this 😎

  9. 2

    Thanks so much for sharing! Love the post & the advice to really nail a channel before moving on.

    1. 1

      Glad you found it helpful ☺️

  10. 2

    This is amazing, Daniel. Thanks for sharing your journey.
    Curious to know when you started working on the KTool - right from idea to launch what that timeline was? It is overwhelming as a founder to stay patient and on track until you start seeing results :)

    1. 2

      I have this idea to build a Kindle tool for a long time.

      On Jan 1, I posted on Reddit asking if somebody would buy such a tool. Someone said yes.

      So I started development on Feb 13, got the first sales in Mar 14.

      It is overwhelming as a founder to stay patient and on track until you start seeing results

      It is but not because of KTool. In the early days, I was already working on another startup (backdrop.io) and a consulting gig. It was a lot of work, but manageable for me.

  11. 2

    Read thoroughly and went through each hyper link, causing to open hyperlinks in hyper links, for a second I got lost on twitter haha.

    Yes, if it was me, I would have googled "KTool reviews" and what it showed, would have believed it, so I think that is something to resolve asap.

    Well done. :D

    -x- This para below, can be ignored -x-
    In the end, I'm an Aeronautical Engineer, designing to build a tool on the side. One of the points I learnt is start talking about your product once you have begun designing it, even if not developing it yet. So, my tool will be around a time saving tool, but I've created a form (50 second read) if you would be interested. Thanks.

  12. 2

    Congrats. happy to see you succeed with the idea :)

  13. 2

    Thanks for sharing.

  14. 2

    Wow! What a story! 🔥🚀

    Even though we communicate daily on Twitter, I still didn't know some of these things 😁😁

    1. 1

      Thank you Amer. Happy to know you on my journey 😁

  15. 2

    Thanks for sharing Daniel
    I will work with this list of questions for our SAAS Tasks Ninja
    Good luck to you!

    1. 1

      Thanks and good luck with Tasks Ninja, Marta. I'm terrible at writing, but I find it easier by answering specific questions like these :D

      1. 1

        I love to work with such questions, it helps to focus!
        Really appreciate your list of questions!
        Also started to follow you on Twitter :)

  16. 2

    Great!!. I always wandering how to gain users from twitter, because I think twitter is also the great community tho

  17. 2

    Congrats! On to 10000...

    1. 1

      Thanks a lot, Mustafa

  18. 2

    I love your story, it's inspiring.

    Still remember the "Fucking supercharged Kindle" headline 😂

    Best of luck Daniel!

    1. 1

      Thank you Marc.

      Haha yeah. I did quite few experiments and some were pretty fun! 😂

    2. 1

      This comment was deleted 12 days ago.

  19. 2

    Thanks for being super transparent!

    1. 1

      Thank you Xavier. Learned a lot from your journey on Twitter 🙏

  20. 2

    I have been following your journey on Twitter and I can say you are one of the indie hackers I have learnt a thing or two from.

    Your progress inspires me to keep going.

    Ps: The KToolGuy part got me 🤣🤣. I shared a newsletter sometime around March this year on how I came up with my SAAS domain name. You can look it up with the link below to see the model I used.



    1. 2

      I've been following your progress on Twitter, and I can say that you are one of the independent hackers I've learned from.

  21. 2

    well done Daniel! you are a true inspiration

    1. 1

      Thanks Dan. I'm not sure about the inspiration part yet haha. But I do hope these learnings would be useful to other indie hackers.

  22. 2

    Great breakdown of your journey, Daniel 💪
    This is indie hacking at its best!

    1. 1

      Thanks a lot Simon. It was your support in the early days that helped KTool gained the exposure I needed 🙏

  23. 1

    Wow congratulations brother, good luck to you. I have a suggestion where you can find a good name and work with the brand: https://www.brandbucket.com/

  24. 1

    I see that you didn't integrated payments earlier. Do you think it could have been a little earlier?

    1. 1

      I shared my thought here https://www.indiehackers.com/post/3-000-ltd-sales-24-mrr-600-registered-users-after-6-months-building-ktool-on-the-side-this-is-my-story-8f8f200f95?commentId=-N8lhcFay8KDCJdZ2jcT

      Looking back, I don’t regret as the Doge was fun and it generated some buzz on Twitter, which was good for marketing :D

  25. 1

    Interesting and fun story. How many months it took to get your first $ from Ktool?

    I see that you didn't integrated payments earlier. Do you think it could have been a little earlier?

    1. 2

      I started coding on Feb 13, got the first sales in Mar 14. So about a month.

      Yeah, I should've integrated payments earlier but I don't regret though. Those development time was spent on building the core feature, which probably helped for earning that first sale.

  26. 1

    @danielnguyen Thanks for these insights! I'm also considering allowing for a few lifetime deal opportunities once I release my product. Is that something you'd recommend, or would use again as a pricing model?

    1. 1

      I would treat LTD as an investment from early adopters.

      It goes both way.

      For them, it’s a risky investment for a new product.

      For me, it provides initial cash influx and product validation I need to continue the development.

      Also providing LTD is a good opportunity for you to ask for early feedback, incentivize them to share it with the community and you got social-proof etc.

      But I would do it only in the beginning, with limited seat. Otherwise, it’s not gonna sustain in the long run.

  27. 1

    thanks for sharing it in detail.

  28. 1

    Thanks for sharing, that's a great progress

  29. 1

    Thanks for sharing the number a Daniel. Surprise that the name is associated with a scammer (since KTool sounds pretty nice to me)

    1. 1

      Yeah. I didn’t put a lot of thought into finding the brand name. Lesson learned 😅

  30. 1

    This is really 👍, facing a problem, solving it and finally monetizing.

    1. 1

      I hope it was helpful to you 😁

Trending on Indie Hackers
I failed 5 startups, what next? 37 comments Users want to use social logins 34 comments Do you have a blog for your business? If not yet, why? 28 comments What I've learned building an indie SaaS business 28 comments How to learn hard things in tech 28 comments 26 actionable marketing tasks you can do right now 14 comments