generated: '2026-08-09'
method: searched
source: https://www.cyclecalcs.com/embed.html
description: >-
  CycleCalcs ships free embeddable sky widgets for third-party sites — six
  iframe widgets that compute in the visitor's browser, plus a
  second-generation host-DOM moon widget that renders directly into the host
  page and reads one cached answer from the public API. No account, no API key
  and no usage limit; the only condition is a visible caption link back to the
  matching CycleCalcs tool.
docs: https://www.cyclecalcs.com/embed.html
loaders:
  - name: widget.js
    url: https://www.cyclecalcs.com/widget.js
    family: host-DOM moon widget (2nd generation)
    async: true
    renders: into the host page inside an isolated style scope, no iframe
    weight: ~10 KB once
    layout_shift: none — the box is reserved before anything loads
  - name: embed.js
    url: https://www.cyclecalcs.com/embed.js
    family: auto-resizing iframe widgets
    async: true
    renders: an iframe that grows and shrinks with its content
families:
  - name: Host-DOM moon widget
    loader: widget.js
    selector: a.cyclecalcs-moon
    shapes: [card, row]
    attributes:
      data-size: card | row
      data-theme: auto | light | dark
      data-lat: optional latitude; omit for a location-free geocentric card
      data-lon: optional longitude
      data-place: display label for the location
      data-key: reserved for the planned per-domain licence (white-labelling)
      data-accent: reserved for the planned per-domain licence
    shows: tonight's phase, illumination, and with coordinates moonrise/moonset
    data_source: the same public /v2 API behind every tool on the site
  - name: Iframe widgets
    loader: embed.js (or a plain <iframe>, no JS required)
    selector: a.cyclecalcs-widget[data-widget]
    base: https://www.cyclecalcs.com/embed/<widget>.html
    options:
      theme: auto | light | dark
      size: card (360px) | compact (300px) | wide (600px)
    widgets:
      - id: moon
        name: Moon Phase Today
        location_required: false
      - id: eclipse
        name: Next Eclipse
        location_required: false
      - id: parade
        name: Planet Parade
        location_required: true
      - id: tonight
        name: What's Up Tonight
        location_required: true
      - id: sun
        name: Sunrise & Sunset
        location_required: true
      - id: clock
        name: Cosmic Clock
        location_required: false
    note: >-
      Widget ids above are inferred from the published moon example
      (/embed/moon.html) and the six named widgets on the page; only the moon
      id is confirmed verbatim in a published snippet.
licensing:
  price: free for any site, personal or commercial
  condition: keep the visible caption link under the widget
  tracking: none
  ads: none
  planned: >-
    A per-domain licence ($29/yr) is announced but not yet live; it would add
    white-labelling (dropping the caption) and a custom accent colour.
    Everything currently free stays free.
csp_requirements:
  iframe_widgets: frame-src https://www.cyclecalcs.com (+ script-src for the JS version)
  host_dom_moon_widget: script-src https://www.cyclecalcs.com and connect-src https://www.cyclecalcs.com