Free tier: Developer tooling

Free tier: Developer tooling

The plumbing between services: API clients and mocks, webhook delivery, scraping, JSON and SQL utilities, and integration tools.

Part of the Free Tier Services Directory.

API clients, testing and mocking

• Beeceptor — Mocks and debugs APIs across REST, SOAP, gRPC and GraphQL without writing code.
• CurlHub — Proxy that records and inspects API calls for debugging. 10,000 requests a month.
• ExtendsClass — Web-based HTTP client for sending requests.
• Hoppscotch — Fast, open API request builder in the browser.
• Insomnia — Open-source API client for designing and testing REST and GraphQL APIs.
• JSONing — Turns a JSON object into a fake REST API, with control over status codes and headers.
• Kreya — Graphical gRPC client that can import APIs through server reflection.
• MockAPI — Mocks up an API and generates plausible custom data behind it.
• Mockerito — Mock REST API with realistic data across nine domains, including e-commerce, finance and healthcare.
• Mockfly — API mocking and feature flag management for development.
• Mocko.dev — Proxies your API and lets you mock chosen endpoints in the cloud while inspecting traffic.
• OpenAPI3 Designer — Builds OpenAPI 3 definitions visually.
• Postman — The widely used API collaboration platform, covering design, testing and documentation.
• RequestBin.com — Creates an endpoint that captures and displays whatever HTTP requests are sent to it.

Webhooks, scheduling and workflows

• AnyHook — Inbound webhook relay: point a Stripe, GitHub or bot webhook at it and it stores each event for inspection or replay.
• Hook0 — Open-source webhooks-as-a-service, so your own product can offer webhooks to its users.
• Inngest — Durable execution and event-driven workflows for TypeScript, Python and Go. Free Hobby plan.
• Posthook — Schedules a webhook to fire at a future time, with retries and delivery tracking.
• PrefectCloud — Orchestration for data pipelines. Five deployed workflows and 500 minutes a month.
• Svix — Webhook sending as a service. Up to 50,000 messages a month.

Web scraping and extraction

• Apify — Scraping and automation platform that turns any website into an API, with ready-made scrapers.
• Browse AI — Extracts and monitors data on the web without code. 1,000 credits a month.
• Data Miner — Browser extension that extracts page data to CSV or Excel.
• Firecrawl — Crawls a site and returns clean Markdown or structured data, intended as input for language models.
• microlink.io — Turns any URL into data: normalised metadata, link previews and screenshots.
• Scraper's Proxy — HTTP proxy API for scraping without managing proxy rotation yourself.
• ScrapingAnt — Headless Chrome scraping API with JavaScript rendering and rotating proxies.
• SerpApi — Scrapes search engine results and returns structured JSON for Google, YouTube, Bing and others.
• Simplescraper — Point-and-click scraping with a webhook after each run. 100 cloud credits.
• Geekflare API — Scrapes pages to Markdown, takes screenshots, and runs TLS and DNS checks.
• WebScraping.AI — Scraping API with built-in parsing, Chrome rendering and proxies. 2,000 calls free.
• wrapapi.com — Turns any website into a parameterised API. 30,000 calls a month.
• Zenscrape — Scraping API with headless browsers and residential IPs. 1,000 requests free.

Databases, JSON and SQL tools

• DB Designer — Cloud database schema design and modelling. Two models free.
• Compare JSON — Compares two JSON structures and shows the differences.
• drawDB — Open-source database diagram editor in the browser, no signup.
• FormatJSONOnline.com — Formats, validates, compares and minifies JSON in the browser.
• JSON to Table — Converts JSON into an interactive table for viewing and editing.
• JSONGrid — Visualises, edits and filters complex JSON in a table grid.
• JSONSwiss — JSON viewer, editor and validator with search and formatting.
• Pixela — Stores a daily number by API and renders it as a heat map, in the style of a contribution graph.
• Sofodata — Turns an uploaded CSV into a secure REST API.
• Sqlable — Collection of SQL tools: formatter, validator and regex tester.

Integration and data movement

• Commerce Layer — Composable commerce API for building and managing orders behind any front end.
• Coupler — Syncs data between applications and builds live dashboards and reports from it.
• Cube — Semantic layer that gives applications consistent access to data across several stores.
• Data Fetcher — Connects Airtable to any API without code, with a Postman-like request interface.
• Dataimporter.io — Connects, cleans and imports data into Salesforce. 20,000 records free.
• Invantive Cloud — Access to more than 70 cloud platforms, including Exact Online, Twinfield and Visma, through one interface.
• Preset Cloud — Hosted Apache Superset for dashboards and exploration. Free for teams of up to five.
• SmartParse — Data migration and CSV-to-API platform.

API management and monitoring

• LoginLlama — Detects suspicious logins and notifies your users.
• Treblle — API log aggregation, observability and governance.
• Trophy — Gamification layer for consumer applications, with prebuilt APIs and open-source UI components.
• Zuplo — API management at the edge, with key authentication and rate limiting. Free tier.

Currency

Compiled September 2026. Free tiers change frequently and nothing here has been independently verified — check the provider before relying on any allowance described above. Entries cover services with a standing free tier, not free trials.

See also

Digital sovereignty, and the other sections of the Free Tier Services Directory.