Nobody wakes up wanting Airtable. They wake up with a spreadsheet that four people edit at once and a vague sense that there should be a better way to hold it. The brand name arrives later, from a colleague or an ad, and from then on every search starts with it. That is a strange way to shop for software: you type the name of the thing you want to leave, and the results are written by the people who want you to stay.
The fastest way to find an open source alternative to any app is to search for the job it does rather than the brand, then check three things on the project's own repository: the licence file, the date of the last release and the price of the hosted plan. Directories such as OpenAlternative, AlternativeTo and the awesome-selfhosted list on GitHub do the first pass for you, and the AppClap catalog count says how wide the field is: of the 8,646 apps live on the site (Oct 28, 2026), 1,019 are open source, 1,447 can be self-hosted and 4,785 have a free tier.
Describe the job, not the brand
Searching for the job you need done finds tools that no “X alternative” list will show you, because the list is organised around the incumbent. “A spreadsheet database like Airtable that I can host myself” is a job. “Airtable alternative” is a brand plus a hope. The first phrasing carries the two constraints that matter to you (a database with a grid view, on your own server) and leaves out the one that does not (whether the vendor was ever compared to Airtable in a blog post).
We can see this working in our own search box. The plain-language searches real people typed into our search box in the last thirty days (web and MCP, our own traffic removed) include “something to send invoices and chase late payments” (six times, 149 results), “simple website analytics I can host myself without cookies” (three times, 88 results), “a help desk that doesn't charge per agent” (two times, 113 results) and “schedule posts to all my social accounts without paying per channel” (two times, 146 results). Each of those sentences contains a pricing constraint, and each one returns a shelf of tools that the brand-name search would have hidden behind the first three sponsored results.
A brand name tells the search engine what you are leaving. A job description tells it what you need. Only the second one can be answered by something you have never heard of.
Where to find open source alternatives to popular software
Four places cover most of the ground, and they are better used together than alone. OpenAlternative lists projects under the heading “Open Source Alternatives to Popular Software,” and shows each one's GitHub stars, licence and last commit, which is exactly the trio you will want to check anyway. AlternativeTo is older and crowd-sourced, covers paid and free tools together, and lets you filter a list down to open source licences. The awesome-selfhosted list on GitHub has about three hundred and thirty thousand stars (Oct 28, 2026) and groups self-hostable software by job, from invoicing to feed readers, with the licence noted on every line. Our own catalog is the fourth: 8,646 web apps you can search in a sentence, with the open source, self-hostable and free-tier flags coming from each tool's own site.
| Directory | What it covers | What it shows per tool |
|---|---|---|
| OpenAlternative | open source twins of paid SaaS | stars, licence, last commit |
| AlternativeTo | all software, paid and free | crowd votes, licence filter |
| awesome-selfhosted | self-hostable software by job | licence, language, demo link |
| AppClap | 8,646 web apps, searched in a sentence | open source, self-host and free-tier flags, price |
None of them is complete, and they disagree with one another, which is useful. If a project appears on all four with the same licence, you can trust the licence. If a project appears on one list as open source and on another as merely self-hostable, read the licence file yourself, because that disagreement usually means something changed.
How do I know if an app is actually open source?
An app is open source when the licence file in its repository is a recognised open source licence, such as MIT, Apache-2.0, GPL-3.0, AGPL-3.0 or MPL-2.0, and not when its homepage says “open.” The file is called LICENSE or LICENSE.md and sits at the top of the repository. GitHub reads it and prints the licence name in the sidebar. When GitHub cannot name the licence, that is the first thing to investigate.
Two cases from this autumn show why the file matters more than the label. n8n, the automation tool, describes itself as “fair-code” and ships under its own Sustainable Use License, with any file carrying “.ee.” in its name reserved for holders of an enterprise licence. You can run it yourself, but it is not open source by the usual definition, and our catalog marks it self-hostable and not open source for that reason. Cal.com was AGPL-licensed open source for five years, then announced on April 14, 2026 that it was going closed source and moving its production code to a private repository; the public code continues as Cal.diy under MIT, without the team features. Both companies are within their rights. The point is that “open source” on a landing page is marketing until the licence file agrees.
Is open source software really free?
Open source software is free to run on your own server, and the same project usually sells a hosted version that is not. The split is the normal business model now, and the hosted price is the number to compare against the incumbent, because that is what you will pay if you do not want to run a server. Cal.diy is free to self-host while Cal.com's Teams plan costs $12 a user a month billed yearly; Rallly is free to self-host while its Pro plan is $6 a seat a month billed yearly; Easy!Appointments is free to self-host while the maintainer's managed hosting is €20 a month billed annually (all checked Oct 28, 2026).
The AppClap flat-price test is the quick way to read those hosted plans: a tool passes when the price on its pricing page is the price on the invoice, with no credits, no per-contact meter and no usage add-ons. All three above pass. The self-hosted route has its own costs, which never appear on a pricing page: a server at a few dollars a month, a backup, updates, and someone's time at the moment the thing breaks.
What the paid version still buys you
The paid incumbent is selling the part of the job you cannot download: a support desk, a compliance report, a sales team that will sign a data processing agreement, and an on-call rotation you are not on. For a company whose scheduling, invoicing or support desk is part of how it makes money, those are real goods, and a per-seat price can be the cheapest way to buy them. The open source alternative is the better deal when the job is important but the stakes of a bad afternoon are low, when your data has to stay on your hardware, or when the incumbent's meter grows faster than your team does.
There is also the licence risk you saw above. A project you adopt as open source can relicense, and the fork that follows may be smaller than the original. That is a reason to prefer projects with a permissive licence and more than one maintainer, not a reason to avoid the category.
- 1Can you describe the job in one sentence without using a brand name?
- 2Does the repository have a recognised licence file, and does GitHub name it in the sidebar?
- 3Is the latest release less than three months old?
- 4Does the hosted plan pass the flat-price test, or does it meter something you cannot predict?
This is the first post in this series that is not about one door in the hallway of paid apps. It is about the hallway itself, and how to read the signs on the doors. We built AppClap because the signs are written for the vendor: a search engine for software should let you type what you need in your own words and show you the owned option next to the one with the biggest brand. Try the method on whatever you are paying for this month. Describe it as you would to a friend, like a spreadsheet database like Airtable that I can host myself, or start from a brand page such as Airtable alternatives and follow the licence column. Then spend thirty seconds on the question that keeps turning up at the end of these posts. Is this a thing you want to rent, or a thing you could own?
