Docs

Fitly API
Reference

Programmatic access to exercises, AI-generated workouts, periodized programs, and a supplement database. Every trainer on Joiinflow gets their own rate-limited API key against this shared dataset.

Base URL

fitly.joiinflow.com/api/fitly

Version

v1

Format

JSON

Auth

API Key

Quick Start

# Fetch 5 exercises using your API key
curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises?limit=5' \
  -H "X-Fitly-Key: wx_your_key_here"

Authentication

Every request requires a key from your API Keys page. Pass it one of two ways.

HTTP HEADER (Recommended)

Keeps the key out of server logs and browser history.

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises' \
  -H "X-Fitly-Key: wx_your_key_here"

QUERY PARAMETER

Convenient for quick tests or embedding a GIF URL directly in an <img> tag.

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises?api-key=wx_your_key_here'

Exercises

GET/v1/exercises

List all exercises with pagination and filters.

Parameters

Name	In	Required
bodyPart	query	No
target	query	No
equipment	query	No
limit	query	No
offset	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises?bodyPart=chest&target=pectorals' \
  -H "X-Fitly-Key: wx_your_key_here"

Example Response

[
  {
    "id": "0025",
    "name": "Barbell Bench Press",
    "bodyPart": "chest",
    "target": "pectorals",
    "equipment": "barbell",
    "difficulty": "intermediate",
    "mechanic": "compound",
    "force": "push",
    "caloriesPerMinute": 7.4,
    "popularityRank": 99,
    "gifUrl": "https://fitly.joiinflow.com/api/fitly/v1/media/videos/0025-EIeI8Vf.gif",
    "isUnilateral": false,
    "recommendedSets": "3-4",
    "recommendedReps": "5-8"
  }
]

GET/v1/exercises/exercise/:id

Get a single exercise by ID.

Parameters

Name	In	Required
id	path	Yes

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/exercise/0001' \
  -H "X-Fitly-Key: wx_your_key_here"

Example Response

{
  "id": "0025",
  "name": "Barbell Bench Press",
  "bodyPart": "chest",
  "target": "pectorals",
  "equipment": "barbell",
  "secondaryMuscles": [
    "triceps",
    "shoulders"
  ],
  "instructions": [
    "Lie flat on a bench with your feet flat on the ground.",
    "Lower the barbell to your chest.",
    "Press back up to full extension."
  ],
  "gifUrl": "https://fitly.joiinflow.com/api/fitly/v1/media/videos/0025-EIeI8Vf.gif",
  "category": "strength",
  "difficulty": "intermediate",
  "mechanic": "compound",
  "force": "push",
  "met": 6,
  "caloriesPerMinute": 7.4
}

GET/v1/exercises/bodyPart/:bodyPart

Filter exercises by body part.

Parameters

Name	In	Required
bodyPart	path	Yes
limit	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/bodyPart/chest?limit=5' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/target/:target

Filter exercises by target muscle.

Parameters

Name	In	Required
target	path	Yes
limit	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/target/biceps?limit=5' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/equipment/:equipment

Filter exercises by equipment.

Parameters

Name	In	Required
equipment	path	Yes
limit	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/equipment/dumbbell?limit=5' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/name/:name

Partial name search.

Parameters

Name	In	Required
name	path	Yes

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/name/squat' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/searchBasic+

Multi-filter search. Requires Basic plan or higher.

Parameters

Name	In	Required
bodyPart	query	No
equipment	query	No
limit	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/search?bodyPart=chest&equipment=barbell' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/bodyPartList

All body part values.

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/bodyPartList' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/targetList

All target muscle values.

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/targetList' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/equipmentList

All equipment values.

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/equipmentList' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/:id/similar

Exercises similar to the given one.

Parameters

Name	In	Required
id	path	Yes
limit	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/0025/similar?limit=5' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/:id/alternatives

Same target, different equipment.

Parameters

Name	In	Required
id	path	Yes
equipment	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/0025/alternatives?equipment=dumbbell' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/:id/calories

Estimate calories burned.

Parameters

Name	In	Required
id	path	Yes
weightKg	query	No
minutes	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/0025/calories?weightKg=80&minutes=15' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/exercises/changesUltra+

Exercises changed since a date. Requires Ultra plan.

Parameters

Name	In	Required
since	query	Yes

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/exercises/changes?since=2026-01-01' \
  -H "X-Fitly-Key: wx_your_key_here"

Workout

GET/v1/workout/generatePro+

Generate a single workout session. Requires Pro plan or higher.

Parameters

Name	In	Required
goal	query	No
duration	query	No
level	query	No
split	query	No
equipment	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/workout/generate?goal=muscle_gain&duration=45' \
  -H "X-Fitly-Key: wx_your_key_here"

Example Response

{
  "goal": "muscle_gain",
  "level": "intermediate",
  "seed": "06vhrfi3",
  "split": "push",
  "bodyFocus": [
    "chest",
    "shoulders",
    "upper arms"
  ],
  "equipment": [
    "barbell",
    "dumbbell"
  ],
  "totalExercises": 5,
  "estimatedDurationMinutes": 47,
  "exercises": [
    {
      "order": 1,
      "sets": 4,
      "reps": "6-8",
      "restSeconds": 90,
      "exercise": {
        "id": "0025",
        "name": "Barbell Bench Press"
      }
    }
  ]
}

GET/v1/workout/programUltra+

Generate a periodized multi-week program. Requires Ultra plan.

Parameters

Name	In	Required
goal	query	No
weeks	query	No
daysPerWeek	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/workout/program?goal=muscle_gain&weeks=8' \
  -H "X-Fitly-Key: wx_your_key_here"

Supplements

GET/v1/supplementsPro+

List supplements. Requires Pro plan or higher.

Parameters

Name	In	Required
goal	query	No
evidence	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/supplements?goal=muscle_gain&evidence=strong' \
  -H "X-Fitly-Key: wx_your_key_here"

Example Response

[
  {
    "id": "creatine-monohydrate",
    "name": "Creatine Monohydrate",
    "category": "performance",
    "goals": [
      "muscle_gain",
      "strength"
    ],
    "typical_dosage": "3-5 g daily",
    "evidence_level": "strong",
    "disclaimer": "Informational content only - not medical advice."
  }
]

GET/v1/supplements/:id

Single supplement by ID.

Parameters

Name	In	Required
id	path	Yes

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/supplements/creatine-monohydrate' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/supplements/exercise/:exerciseId

Supplements relevant to a given exercise.

Parameters

Name	In	Required
exerciseId	path	Yes

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/supplements/exercise/0025' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/supplements/filters

All filter values with counts.

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/supplements/filters' \
  -H "X-Fitly-Key: wx_your_key_here"

GET/v1/supplements/stackUltra+

Goal-based stack builder. Requires Ultra plan.

Parameters

Name	In	Required
goal	query	Yes
level	query	No

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/supplements/stack?goal=fat_loss' \
  -H "X-Fitly-Key: wx_your_key_here"

Account

GET/v1/plans

Your own full plan ladder (not just the calling key's tier) - what your app renders its pricing page from.

Example Request

curl 'https://fitly.joiinflow.com/api/fitly/v1/plans' \
  -H "X-Fitly-Key: wx_your_key_here"

Rate Limits

Each key has a request quota tied to its plan. Free is a lifetime total that never resets; every paid plan resets monthly. Exceeding it returns 429.

// HTTP 429
{
  "error": "quota_exceeded",
  "limit": 500,
  "used": 501,
  "resetAt": null,
  "message": "You have exceeded your plan's request quota."
}

Error Codes

Every error returns JSON with an error field.

Status	Error	Cause
`401`	missing_api_key / invalid_api_key	No key provided, or the key is invalid/revoked.
`403`	plan_required	Your plan doesn't include this endpoint. See `requiredPlan` in the response.
`404`	not_found	The requested ID doesn't exist.
`429`	quota_exceeded	You've used your plan's full request quota.

Plans

All plans include the full exercise catalog. Higher tiers unlock search, workout generation, and supplements.

Plans are per-trainer, not fixed platform tiers, the ones below are a starting template every trainer gets by default, editable from your own Plans page. Fetch your own live pricing programmatically via GET /v1/plans.

Free

$0/mo

✓500 requests total
✓Core exercise endpoints
✓10 results per page

Basic

$9.99/mo

✓10,000 requests / month
✓Multi-filter search
✓20 results per page

Pro

Popular

$29.99/mo

✓100,000 requests / month
✓AI workout generator
✓Supplements database
✓50 results per page

Ultra

$79.99/mo

✓1,000,000 requests / month
✓Periodized programs
✓Joint & Rehab metadata
✓Supplement stack builder
✓100 results per page

Need more volume? Enterprise plans are available, contact us from the Billing page.

Fitly APIReference

Authentication

HTTP HEADER (Recommended)

QUERY PARAMETER

Exercises

Parameters

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Example Response

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Example Response

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Workout

Parameters

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Example Response

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Supplements

Parameters

Example Request

Example Response

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Parameters

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Account

Example Request

Rate Limits

Error Codes

Plans

Fitly API
Reference