Independent: paid links never change the order. Every fact checked with the vendor.

How we review
stackwijsSearch software…Search
Submit a tool

What should you look for in developer tools and APIs?

You build an API into your own product, so you do not choose it only on today's price. Look at how the costs grow with your usage, where your customers' data ends up and how easily you can switch again later.

  1. Cost per credit, message or account

    APIs usually charge by usage: credits, messages, connected accounts or users. Work out what you pay at ten times as much traffic, because there is often a big jump between two plans there.

    Ask the vendor

    What does an extra credit or message above my bundle cost, and what happens if I use it up halfway through the month?

    Sort by lowest price5 of 6 tools have a public price

  2. Free plan to build on

    With a permanent free plan you build and test your integration without a credit card. Do look at the rate limits and the number of concurrent requests, because they determine whether you can also run a small production app on it.

    Ask the vendor

    Which rate limits and how many concurrent requests do I have on the free plan, and may I use it commercially?

    Show tools with a free plan5 of 6 tools meet this

  3. A free trial of the paid plan

    Some features, such as reviews on private repositories or a higher limit, are only in a paid plan. A free trial lets you test them on your own code or data before you start paying per user.

    Ask the vendor

    Can I try the paid plan on my own project, and does the trial stop by itself without any charges following?

    Show tools with a free trial1 of 6 tool meets this

  4. Where your users' data is stored

    If your app sends names, email addresses or messages of your customers to an API, that data goes with it to the vendor's servers. With an American vendor you have to check whether they fall under the Data Privacy Framework, and mention that in your own privacy statement.

    Ask the vendor

    In which region does the API process my requests and logs, and can I choose an EU region?

    No tool in the guide says this yet.More about data in the EU

  5. Data processing agreement and sub-processors

    If the API processes personal data of your customers, the vendor is your sub-processor. You then need a data processing agreement and a list of sub-processors you can show to your own customers. Note: with some APIs you only get that from a more expensive plan.

    Ask the vendor

    From which plan do I get a data processing agreement, and where is the current list of sub-processors?

    No tool in the guide says this yet.More about the data processing agreement

  6. SDKs, MCP and integrations

    An official SDK in your language and an MCP server for AI agents save you a lot of your own code. Integrations with n8n, Zapier or your code platform also let you use the tool without building everything yourself.

    Ask the vendor

    Is there an official SDK for my programming language, an MCP server, and how long does an old API version keep working?

    Sort by most integrations6 of 6 tools list integrations

  7. Suitable for a sole trader or small team

    Many developer tools are made for large teams, with prices per user or a high entry price after the free plan. Check whether there is a plan that suits a freelance developer or a software company with a few people.

    Ask the vendor

    Is there a plan for one developer or a small team, and am I tied to an annual contract?

    Show tools with a plan for freelancers5 of 6 tools meet this

  8. Switching again or self-hosting

    If you build an API deep into your product, switching later is expensive. Open-source tools you can host yourself give you a way out if the price rises or the service stops, and let you keep the data in your own EU environment.

    Ask the vendor

    Can I host the software myself, and how do I export my data and settings if I stop?

    We do not have a filter for this yet. Ask the vendor.

Frequently asked questions about choosing developer tools

What should you look for in developer tools and APIs?

Look mainly at cost per credit, message or account, free plan to build on, a free trial of the paid plan, where your users' data is stored, data processing agreement and sub-processors, SDKs, MCP and integrations, suitable for a sole trader or small team and switching again or self-hosting. For each point we explain why it matters and which question to ask the vendor.

Which questions should you ask a vendor of developer tools?

What does an extra credit or message above my bundle cost, and what happens if I use it up halfway through the month? Which rate limits and how many concurrent requests do I have on the free plan, and may I use it commercially? Can I try the paid plan on my own project, and does the trial stop by itself without any charges following? In which region does the API process my requests and logs, and can I choose an EU region?

How many developer tools in the guide can you use or try for free?

Of the 6 developer tools in our guide, 5 have a free plan and 1 can be tried for free, according to the vendor's site.

Sources

  1. Autoriteit Persoonsgegevens: Transferring personal data to the US (in Dutch)
  2. Autoriteit Persoonsgegevens: Transferring personal data outside the EEA (in Dutch)
  3. Autoriteit Persoonsgegevens: Data processing agreement (in Dutch)

Texts and sources checked on . The counts follow from the facts in the guide. Rules can change; the source prevails. This is an explanation, not legal or tax advice.

We get a fee if you take out a subscription through us. That does not change our verdict.