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RepDB
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.
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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.
Based on our record, JSONLint seems to be more popular. It has been mentiond 138 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
I've been maintaining jsonlint.com for years. It's a simple JSON validator that I enjoy hacking on every now and then. Nothing fancy, just a useful tool that developers seem to appreciate. - Source: dev.to / 6 months ago
Note: It is crucial that your batchinput.jsonl file is correctly formatted. You can use online JSON formatters and validators like jsonformatter.org or jsonlint.com to verify its integrity before proceeding. - Source: dev.to / 10 months ago
Online Tools: Websites like JSONLint or jsonformatter.org let you paste JSON and get a minified version instantly. - Source: dev.to / 11 months ago
Or paste your JSON into JSONLint. Both tools immediately identify stray control characters. - Source: dev.to / over 1 year ago
Our old pal VS Code will probably throw up some wiggly red lines if we do it wrong, so look out for them. If you're struggling to see why it doesn't work, try an online JSON Validator and see if it pushes you in the right direction. - Source: dev.to / over 1 year ago
JSONFormatter.org - Online JSON Formatter and JSON Validator will format JSON data, and helps to validate, convert JSON to XML, JSON to CSV. Save and Share JSON
JSON Formatter & Validator - The JSON Formatter was created to help with debugging.
JSON Editor Online - View, edit and format JSON online
FreeFormatter - Freeformatter is a platform that contains free online tools for developers, including formatters (json, html, xml, sql, etc.), minifiers (css, javascript), compactors, validators, and much more.
Code Beautify JSON Validator - Code Beautyโs JSON Validator or JSON Lint is easy to use tool to copy, paste and validate JSON data.
DevToys - A collection of converters, formaters, encoders, generators and other tools for your Windows desktop.