Conversion Tracking

Overview

Conversion tracking answers the question a click count cannot: which link produced the signup or the sale. When a link has the toggle on, the redirect hands each human click an unguessable id and appends it to your destination as ?flyn_id=...; your site (or your affiliate network) sends that id back when the visitor converts, and the conversion, with its value, lands on the exact link that earned it.

Turn it on for a link

Tracking is per link and off by default. Only links with it on carry a click id, so every other link's destination URL stays untouched.

1. Create or edit a link, then flip Conversion tracking in the editor.
2. Or set conversionTracking: true on POST /api/links or PATCH /api/links/:id.

curl -X POST https://www.flyn.to/api/links \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://example.com/pricing",
    "conversionTracking": true
  }'

Switching the toggle off silences the endpoint for that link immediately: pings then answer 404. The link object also returns conversions, conversionValueCents and conversionCurrency.

The browser tag

The tag is served from https://www.flyn.to/flyn.js. It is identical for every site, so there is no id to configure.

1. Site-wide, on every page

<script src="https://www.flyn.to/flyn.js" defer></script>

On any page load, if the URL carries ?flyn_id= the tag stores it in a first-party cookie and in localStorage, then removes the parameter from the address bar with history.replaceState. Last click wins. Storage is requested for 90 days, though Safari caps script-set storage nearer 7.

2. On the thank-you page

Use this variant instead of the plain one on the page a customer reaches after converting. Every data- attribute except data-conversion is optional.

<script src="https://www.flyn.to/flyn.js"
        data-conversion
        data-value="49.00"
        data-currency="USD"
        data-event="sale"
        data-txid="ord_10231"
        defer></script>

3. From your own code

Use this when the value is only known at runtime (a cart total, a plan price) or when the goal is not a page load at all.

window.flyn('conversion', {
  value: 49.00,
  currency: 'USD',
  event: 'sale',
  txid: 'ord_10231',
});

The call returns false when no click id is stored, which is the normal case for a visitor who did not arrive through a tracked link. It fires once per (event, click) per browser session, so a refreshed thank-you page does not re-send; the server dedupes as well. The body is sent via navigator.sendBeacon, falling back to fetch with keepalive, as a plain text body so the request stays a CORS simple request that needs no preflight.

The server postback

For affiliate networks and any backend that confirms the sale server-side. /api/postback is the same handler as /api/conversion under the name every tracker uses, so a postback URL template pasted from network docs works as-is.

This is runnable as-is once you swap in a real click id:

curl "https://www.flyn.to/api/postback?click_id=V1StGXR8_Z5jdHi6&event=sale&value=49.00&currency=USD&txid=ord_10231"

{
  "ok": true
}

The same call as JSON, for a backend that would rather POST:

curl -X POST https://www.flyn.to/api/conversion \
  -H "Content-Type: application/json" \
  -d '{
    "click_id": "V1StGXR8_Z5jdHi6",
    "event": "sale",
    "value": 49.00,
    "currency": "USD",
    "txid": "ord_10231"
  }'

To wire this to a network, pass the click id into the network's subid field on your destination URL and put their click-id macro where click_id goes. POST accepts JSON, form-encoded and plain-text bodies; query parameters are merged underneath the body as a fallback, so both transports work.

Parameters

The same set for every transport: the tag, POST /api/conversion, and the GET postback.

There is deliberately no ref alias for event. Postback URLs commonly carry &ref= as a referral tag, which would silently rename the event and fragment the dedupe key into one conversion per distinct ref value.

Status codes

The tag never reads the response, so a browser-side mistake is silent. When you are debugging an integration, send the same payload with curl and read the status.

Refunds

A refund is a conversion with a negative value. It subtracts from both the link's conversion count and its total value.

curl "https://www.flyn.to/api/postback?click_id=V1StGXR8_Z5jdHi6&event=refund&value=-49.00&currency=USD&txid=ord_10231"

curl "https://www.flyn.to/api/postback?click_id=V1StGXR8_Z5jdHi6&event=sale&value=-49.00&currency=USD&txid=ord_10231_refund"

Keep the currency the same as the original sale. See the currency note under Limits for why.

Limits

Further reading

• Conversion tracking, the feature page , what it does, who it is for, and how it reads in the dashboard.
• Postback URL tracking: how S2S conversion tracking works , the per-network macro dialects and the reasons postbacks usually fail.
• How to track which posts drive sales, not just clicks , the measurement method, including how many clicks you need before the answer means anything.
• Click Analytics , the click side of the same data: the denominator your conversion rate is computed against.