Software Alternatives & Startups

Readwise VS Calcumber

Compare Readwise VS Calcumber and see what are their differences

Readwise

Effortlessly rediscover and organize your Kindle highlights

Rating
5.0 · 1 review
Calcumber

Calculate in a notebook and share — from everyday math to engineering.

Rating
0 reviews
Pricing
Free
Note: These products don't have any matching categories. If you think this is a mistake, please edit the details of one of the products and suggest appropriate categories.

Which is more popular?

Based on our record, Readwise seems to be more popular. It has been mentioned 88 times since March 2021.

social mentions
88 vs 0
Productivity popularity
100% vs 0%
alternatives listed
240+ vs 7

Base details

Website, pricing, platforms and company facts side by side.

Readwise
Calcumber
Website readwise.io calcumber.app
Pricing
Free
Platforms —
Web Windows Linux Mac +1
Company — Startup from Switzerland · 1 - 9 employees · 2025
Listed in

About Readwise and Calcumber

In their own words, as submitted to SaaSHub.

Readwise
Calcumber

No description of Readwise yet.

Use variables, functions, and units and see results immediately. Add comments, copy calculations to apps like Word or Excel, or share them through an editable link. Calculate thermodynamic fluid properties with the integrated CoolProp library.

Read more about Calcumber

Features and specs

What each product offers, as listed by its team.

Readwise 5 features
Calcumber 7 features
  • Centralized System
    Readwise allows users to consolidate highlights and notes from various reading platforms, such as Kindle, Instapaper, and Pocket, into one place.
  • Ease of Use
    The platform is user-friendly, making it easy to import, organize, and review highlights.
  • Spaced Repetition
    Readwise uses spaced repetition algorithms to help users retain and recall information over time by regularly revisiting highlights.
  • Customizable Export Options
    Users can export their highlights and notes to other services like Evernote, Notion, or plain text files, allowing for flexible usage of the stored data.
  • Search Functionality
    Readwise offers robust search capabilities, making it simple to find specific highlights or notes across your library.

Possible disadvantages

  • Subscription Cost
    Readwise operates on a subscription model, which may be considered expensive for some users relative to the features offered.
  • Limited Functionality Without Subscription
    While there is a free trial available, many features are gated behind a subscription, limiting the usability of the free version.
  • Learning Curve
    Despite its overall user-friendliness, some users might find a learning curve when initially setting up and configuring the system to suit their needs.
  • Dependence on Third-Party Integrations
    Readwise’s value is largely dependent on its integrations with third-party services, meaning any changes or issues with those services can impact its effectiveness.
  • Privacy Concerns
    Since Readwise collects and stores data from multiple reading platforms, there may be privacy concerns regarding how this data is handled and stored.
  • 🌿 Naturally type expressions
    get immediate results
  • 🔗 Copy and share
    keep calculations editable with a link
  • 🧩 Variables and constants
    pi, e, G, mu0
  • 🧪 Scientific functions
    sin, acos, log, round, and more
  • ♨️ Thermodynamic fluid properties
    refrigeration, heat pumps, steam and air
  • 💡 Installation optional
    run directly in your browser
  • 📱 Multi-platform
    WebApp, Windows, more to come

Analysis

An editorial look at what each product does well and who it suits.

Readwise
Calcumber

Overall verdict

  • Overall, Readwise is well-regarded for its utility in helping users actively engage with and digest their reading materials. It provides a streamlined way to revisit and reinforce key concepts, making it a valuable tool for those serious about boosting their information retention.

Why this product is good

  • Readwise is designed to help users retain information from their readings by organizing, highlighting, and revisiting key excerpts. It integrates with various platforms like Kindle, Instapaper, and Pocket to collate highlights in one place. The daily review feature encourages consistent engagement with past highlights, aiding in better recall and comprehension. The platform is beneficial for avid readers, students, and professionals who wish to maximize their learning retention and make the most out of their reading habits.

Recommended for

  • Avid readers looking to remember more from their books
  • Students who need to recall key concepts from academic materials
  • Professionals who want to maintain a repository of valuable insights from articles and reports for reference
  • Anyone interested in personal development and continuous learning through reading

No analysis of Calcumber yet.

Videos

Walkthroughs and reviews on video.

Readwise 2 videos + Add
Calcumber 0 videos + Add

Readwise: How to use Spaced Repetition with your books

More videos

  • - Keep track of Kindle highlights with Readwise [#49] Adam Franklin

No Calcumber videos yet. You could help us improve this page by suggesting one.

Category popularity

How often each product is chosen within a category, 0–100% relative to the other.

Score bands 0–20 21–40 41–50 51–60 61–100
Readwise
Calcumber
100% 100%
0% 0%
0% 0%
100% 100%
100% 100%
0% 0%
0% 0%
100% 100%

Questions & Answers

As answered by people managing Readwise and Calcumber.

Why should a person choose your product over its competitors?

Calcumber's answer:

  • Sharing calculations and embedding them in documents or web pages is perfect for education.
  • Natural unit support, just include them in your expression and Calcumber handles it.
  • Free and easy access to thermodynamic fluid-properties.

What makes your product unique?

Calcumber's answer:

  • Easy to use calculator notebook
  • From simple arithmetic to advanced engineering with units
  • Installation optional
  • Send calculation link with full privacy
  • Embed calculation templates, exercices and soultions in documents or interactively in web pages

What's the story behind your product?

Calcumber's answer:

When starting for a Master of Advances Study in Energy Systems, I was looking for a suitable state-of-the-art calculator. Then I built my own Calculator Calcumber and now the Eastern Switzerland University of Applied Sciences is using Calcumber for teaching students in thermodynamics.

How would you describe the primary audience of your product?

Calcumber's answer:

  • The notebook-style calculator is great for everybody who wants more than just a single line calculator.
  • The sharing and embedding features make it Calcumber very well suited for teachers and students. The power of consistently using units is shown immediatly.
  • Engineers will like the unit support, sharing calculations with collegues and if needed the built-in fluid properties calculation.

Which are the primary technologies used for building your product?

Calcumber's answer:

HTML, CSS, TypeScript, PWA, CoolProp

Who are some of the biggest customers of your product?

User comments

Share your experience with using Readwise and Calcumber. For example, how are they different and which one is better?

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Reviews and articles

External articles and on-site reviews we used to compare the two products.

Readwise 5.0 · 1 review
Calcumber no reviews yet
  • Great help to review books
    SaaSHub review
    · Nov 2021

    I imported my kindle highlights, as many others. Now I daily review some highlights (thanks to a dashboard, I am motivated). And where I didn't create highlights, as I only listened to the audiobooks, I get the...

We have no reviews of Calcumber yet. Be the first one to post

Social recommendations and mentions

Recommendations tracked on public social media and blogs since March 2021.

Readwise 88 mentions
Calcumber 0 mentions
  • Relego, a free, self-hostable alternative to Readwise
    Anyway, as I reached the end of the chapter, I wanted to read my Readwise's daily recap. However, my iPhone was in other room. I didn’t want to get up; I was tired. - Source: dev.to / 4 months ago
  • Exporting Mac OSX Book Highlights into an Obsidian Vault or Markdown Files
    The only highlights that Readwise retrieves semi-automatically are from the books I buy from Kindle, by going into the Readwise app and clicking a button. If I upload them to Kindle or need highlights from the Apple Books app, I have to... - Source: dev.to / almost 2 years ago
  • Show HN: I combined spaced repetition with emails so you can remember anything
    Readwise also has this feature. I get a daily email with a random assortment of highlights that have been pulled in from multiple sources (Reader, Notion, Kindle, etc.) The product benefit in their case is that it's kind of like Zapier,... - Source: Hacker News / almost 2 years ago

View more

Tracking Calcumber since Jul 2026.

Alternatives to Readwise and Calcumber

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