MuscleWiki API vs the API Ninjas Exercises API

API Ninjas sells a large catalogue of small, single-purpose APIs on one key. Its Exercises API is a text endpoint: no video, no GIFs and no images.

Sources: API Ninjas: pricing page, API Ninjas: Exercises API documentation

The API Ninjas Exercises API returns exercise text: name, type, muscle, difficulty, equipment, instructions and safety notes, with no media field of any kind. Ours is a media product: 7,766 MP4 clips across 1,943 exercises, male and female, front and side, plus 15,144 bodymap images and curated routines and workouts on the higher plans. We serve 14 languages at parity where their documentation describes no language parameter, and every paid plan of ours carries commercial-use rights from the first call, where their free tier prohibits commercial use outright. If your product will never render a demonstration, this page will not help much. If it will, there is nothing on their side to put next to ours.

Sources: API Ninjas: Exercises API documentation, API Ninjas: pricing page

Every claim about another vendor on this page was fetched from that vendor’s own public documentation. This one was verified 14 September 2026. Figures change; if you are reading this long after that date, check the linked sources before you rely on it.

Side by side

Every figure in the API Ninjas column links to the page we read it on. Where we could not fetch a fact from a public source, there is no row for it.

The MuscleWiki API and API Ninjas Exercises API compared across 11 axes, with a source link for every claim about API Ninjas.
AxisMuscleWiki APIAPI Ninjas
Media in the response7,766 MP4 clips: 4 for every exercise, male and female, front and side. Every clip carries a matching thumbnailNone. The documented response fields are name, type, muscle, difficulty, instructions, equipments and safety_info. There is no image, GIF or video fieldSource: API Ninjas: Exercises API documentation
Exercises in the catalogue1,943 exercises, every one with video (counted 10 September 2026)"over 3000 exercises targeting every major muscle group"Source: API Ninjas: Exercises API documentation
Commercial use on the free tierOur free plan is Playground-only, so there is nothing to use commercially. Every paid plan includes commercial-use rights, against two required attribution items that apply on all plans"Commercial use of the Exercises API is not permitted on the free tier", and the free tier requires attributionSources: API Ninjas: Exercises API documentation, API Ninjas: pricing page
Caching rightsStable, deterministic media URLs. Caching allowance: text metadata up to 30 days, thumbnails 24 hours on-device only, video and bodymaps served no-storeData caching and storing is allowed on Business and above; it is not allowed on the Developer or Free plansSource: API Ninjas: pricing page
Languages14 languages at parity: every exercise carries its name in all 14 and returns the same instruction steps in all 14, so no language returns a thinner record than English (non-English needs the Growth plan or higher)Their Exercises API documentation describes no language parameter and shows English responses onlySource: API Ninjas: Exercises API documentation
Routines and workouts32 curated routines and 92 workouts as read-only API resources, with sets, reps and exercise references (Professional plan or higher)Not part of the Exercises API: the two documented endpoints are an exercise search and a name-only list by muscle groupSource: API Ninjas: Exercises API documentation
Results per requestPaginated list endpoints that return full records, plus filter and search endpoints across every field/v1/exercises returns up to 5 full records per request, documents no limit, and marks offset Premium only. /v1/allexercises does take limit (default 10, maximum 100) but returns a JSON array of exercise *names* and is "Business tier and above, or any annual plan"Source: API Ninjas: Exercises API documentation
Difficulty metadataPresent on every exercise (Novice, Beginner, Intermediate, Advanced)difficulty: beginner, intermediate or expertSource: API Ninjas: Exercises API documentation
Rate limitingA monthly quota on the data and media endpoints rather than a request rate; over-quota requests return 429 with Retry-After. Minting a media token is the one rate-limited call, at 10 a minute per keyThe free tier is limited to 100 API calls per hour; the paid plans list no rate limitSource: API Ninjas: pricing page
AuthenticationA single X-API-Key header on every request. Your server can exchange that key for a short-lived media token, so a native player fetches /stream/ URLs with no header and the key never ships inside an app binaryX-Api-Key headerSource: API Ninjas: Exercises API documentation
Bodymap images15,144 bodymap images showing the muscles a movement works, in light and dark themes, front and back (Professional plan or higher)Not offered by the Exercises APISource: API Ninjas: Exercises API documentation

Sources for our column

Exercise, video, language and bodymap counts all come from the dataset the API serves. Every figure in the API Ninjas column links to the page it came from, in the cell that makes the claim.

Where the MuscleWiki API and API Ninjas differ

The handful of differences that actually decide it, and what each one costs whoever picks the other side.

There is no media field in their response
The documented response fields for their Exercises API are name, type, muscle, difficulty, instructions, equipments and safety_info. No image, GIF or video field appears anywhere in it. Everything else on this page follows from that, and so does the reason this comparison does not put the two monthly prices side by side: a text endpoint and a video library are not the same purchase.Source: API Ninjas: Exercises API documentation
Five records to a page
Their /v1/exercises endpoint returns up to 5 full records per request, documents no limit parameter and marks offset as Premium only. The one that does take a limit of 100, /v1/allexercises, returns exercise *names* rather than records, and it is "Business tier and above, or any annual plan". So a twenty-item screen costs four calls. Ours is one call, one screen.Source: API Ninjas: Exercises API documentation
Commercial use and caching are gated on their side too
Their documentation states that "Commercial use of the Exercises API is not permitted on the free tier", and their free tier requires attribution. Caching and storing their data is allowed on Business and above, not on Developer or Free. Every paid plan of ours includes commercial-use rights from the first call and the same caching allowance. We ask for two things in return, on every plan: a verbatim disclosure in your Terms of Service or Privacy Policy, and the MuscleWiki branding left visible in the video you display.Sources: API Ninjas: Exercises API documentation, API Ninjas: pricing page, MuscleWiki API Terms: §8 Attribution
One key covers dozens of their APIs
Exercises is one endpoint in a large catalogue that also covers nutrition, finance, geography and plenty besides, all on one key and one plan. If you need several of those, one vendor and one invoice is a real saving. We sell exercise data and nothing else.Source: API Ninjas: Exercises API documentation
They ship an MCP server too
Their site advertises an MCP server for connecting AI agents to their APIs, so first-party MCP support is not something we have to ourselves. Ours is npx @musclewiki/mcp: it forwards every call using your own key, so your plan, your quota and your terms apply unchanged.Source: API Ninjas: Exercises API documentation

Moving an existing API Ninjas integration to us

What actually changes in your code.

Most of the work is adding media
Their response has no media, so most of the integration is new work rather than a rename: rendering video, picking the male or female variant and the front or side angle, and deciding where a bodymap image belongs in your UI.Source: API Ninjas: Exercises API documentation
Field mapping
muscle becomes our primary_muscles array and equipments becomes category. Their instructions, a single string, becomes our steps array, and type maps loosely onto mechanic and force. Their safety_info has no equivalent in our schema.Source: API Ninjas: Exercises API documentation
Auth and paging
X-Api-Key becomes X-API-Key, which is the easy half. Paging is the part that touches your code: the five-record ceiling and the names-only bulk endpoint both go away, so the screen that took four calls takes one. Cost is metered per request, and expanded endpoints report theirs in the X-API-Calls-Cost header.Source: API Ninjas: Exercises API documentation
Re-read the caching rules before you port your cache layer
If you were caching their data on a Business plan, our terms are different, and ours are the same on every paid plan: text metadata up to 30 days, thumbnails 24 hours on-device only, video and bodymaps served no-store.Source: API Ninjas: pricing page

You can try every endpoint in the Playground before you commit, read the documentation, or check what each plan reaches on pricing.

Other comparisons