
Loadster
Loader.io
LoadForge
k6 Cloud
LoadUIWeb
LoadFocus
Loadium
LoadStorm
RepDB
Loadster is a cloud-based load testing and synthetic monitoring platform for engineers who want to know how their applications behave under real traffic.
Tests run with three types of bots: Protocol Bots for HTTP testing, headless Browser Bots that render full pages and execute JavaScript in real Chrome browsers, and Playwright bots for when you want to use Playwright JS directly.
Loadster scripts can be recorded from Chrome or Firefox with the Loadster Recorder extension, edited in a built-in editor with variables, datasets, and shared includes, and then replayed from multiple cloud regions.
Each test run returns detailed page timings (TTFB, FCP, LCP, CLS, etc) alongside resource waterfalls, screenshots, and full traces you can step through in a self-hosted trace viewer. Tests scale from a handful of virtual users (bots) to hundreds of thousands across distributed cloud engines without you provisioning anything.
The same scripts can be set up as monitors that run on a schedule from chosen regions. Notification policies route incidents to email, SMS, voice, or integrations like Slack and PagerDuty. Projects, roles, and shared test history keep teams aligned on what passed, what failed, and what changed.
Pricing is usage-based via Loadster Fuel, with 50 free units on sign-up and no credit card to start.
RepDB is a one-time-purchase exercise dataset for developers building fitness and workout apps โ not a subscription, not a rate-limited API. You download the data once and own it: JSON (and SQLite on the higher tier), WebP images, and full EN/DE/ES translations, with no per-request billing and no dependency on our servers staying up.
A free tier includes 400 exercises with flat-style 512ร512 images, attribution-licensed for commercial in-app use. The Starter tier ($199) adds the full catalog in classic white-background style. Standard ($399) adds transparent 1024px images, looping animations, exercise relations (similar/progressions/regressions), workout templates, and embeddings โ exclusive to that tier.
Every exercise includes muscle-group highlighting, equipment/muscle icons, MET values, and safety/goal tags. Compared to GIF- or JPG-based competitor APIs, RepDB images are transparent WebP with no watermarks, so they drop into any app UI without a white box around them.
Loadster
RepDBRepDB's answer:
RepDB is sold as a one-time download, not a metered API โ you own the JSON/SQLite data and WebP images outright, with no rate limits, no per-request billing, and no risk of the vendor cutting off access. It's also the only dataset in this space with EN/DE/ES translations, transparent (alpha-channel) images with no watermark, muscle-group highlighting, safety/goal tags, and looping animations on the higher tier.
RepDB's answer:
RepDB grew out of a consumer workout app its creator was building solo. Sourcing exercise images and data meant either paying for a subscription API with usage caps and no caching rights, or producing everything from scratch. The illustrated, multi-language dataset was built for us first, then split out as its own product once it became clear other indie developers had the same problem and preferred to buy the data outright rather than rent it through an API.
RepDB's answer:
Most alternatives are subscription APIs โ you pay monthly, you're capped on requests, and ExerciseDB's terms of use explicitly forbid caching or storing the data at all, so every image render is a live paid API call. RepDB is the opposite: pay once, download the files, self-host with zero ongoing dependency. It's also the only option offering true DE/ES localization and transparent images instead of a white box behind every exercise.
RepDB's answer:
Solo developers and small teams building fitness or workout-tracking apps (iOS, Android, web) who need licensed exercise images and structured exercise data, but don't want to build their own media pipeline or depend on a rate-limited third-party API.
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