# Custom Tokens > Build your own value for every click and send it to your offers, landers, and traffic sources. This page shows you how to build custom tokens: values of your own that Proferex creates for every click from a template you write. A custom token is useful when you want to send a value that no single traffic source variable gives you. A common example is a sub ID for your offer source that combines the traffic source's campaign and zone, such as `9921_48211`. Your offer source then shows which campaigns and zones convert, in its own reports. Each click can carry three custom tokens. You use them as `{custom_token}`, `{custom_token2}`, and `{custom_token3}`. --- ## How a custom token gets its value You set up a custom token on a campaign with one or more **definitions**. Each definition has a template, such as `{v2}_{v1}`. On every click, Proferex: 1. Picks one active definition for the token. With more than one, it picks at random, weighted by their **Weight**. 2. Fills in the template with the click's values. For a click with `48211` in v1 and `9921` in v2, `{v2}_{v1}` becomes `9921_48211`. 3. Applies any [value transformations](#value-transformations). 4. Saves the result with the click. Proferex does this for each of the three tokens on its own. If a campaign has no active definition for a token, it uses the default template on its traffic source. See [Default custom token templates](/docs/tracker/traffic-sources/index.md#default-custom-token-templates). --- ## Add a definition Open the campaign and go to its **Custom Tokens** tab. The **Token Definitions** card lists the campaign's definitions. ![The Custom Tokens tab of the campaign Push - US - Mobile, with two definitions for Token 1: Zone ID with the template v1, active at 100 percent, and Zone + Country with the template v1_country, inactive](/images/docs/custom-tokens-definitions.jpg "A campaign's custom token definitions") Click **Add Definition**: ![The Create Custom Token Definition form with Token 1 selected, the name Campaign + Zone, the template v2_v1, the list of tokens to add, a weight of 100, and Active turned on](/images/docs/custom-tokens-definition-form.jpg "A definition that joins the traffic source's campaign and zone") | Field | What it does | |---|---| | **Custom token** | Which token the definition fills: Token 1 for `{custom_token}`, Token 2 for `{custom_token2}`, or Token 3 for `{custom_token3}`. | | **Name** | A name you will recognise, such as `Campaign + Zone`. | | **Template** | Your own text, placeholders, or both. Click a token under **Click to add tokens** to add it. | | **Weight (for random selection)** | How often this definition is picked compared with the token's other active definitions. `0` turns it off. | | **Active** | Turn it off to stop using the definition without deleting it. | Click **Create**. New clicks use the definition straight away. Clicks already recorded keep the value they had. **Pick**, next to **Name**, copies the name and template from a definition in another campaign. ### What a template can use A template can use the campaign's values, such as `{campid}`, `{campid_short}`, `{campaign_slug}`, `{landerid}`, `{offerid}`, and `{trafficsourceid}`. It can also use the traffic source's values, `{v1}` to `{v10}`, `{externalid}`, and `{cpc}`, and the visitor's location and device, such as `{country}`, `{city}`, `{device_type}`, and `{os}`. A template can't use `{clickid}` or another custom token. If the click has no value for a placeholder, the placeholder stays as written. For example, `{v3}_US` stays `{v3}_US` when the traffic source sent no v3. --- ## Test two values against each other Give one token two active definitions with the same weight, such as `angle-a` at 50 and `angle-b` at 50. Each value then goes to about half of the clicks. The **Distribution** column shows each definition's share. --- ## Value transformations A value transformation swaps one value for another before it is saved. Use it when a partner expects a different value than the one your template produces, or to hide a raw ID. Under **Value Transformations**, click **Add Transformation**. ![The Create Transformation form with Token 1 selected, the From Value 1048211, and the To Value zone-a](/images/docs/custom-tokens-transformation.jpg "Turn one value into another") 1. Pick the **Custom token**. 2. Enter the **From Value**, the value to replace. 3. Enter the **To Value**, the value to use instead. 4. Click **Create**. The **From Value** must match the whole value exactly, including capital letters. Transformations can follow each other: if `a` becomes `b`, and `b` becomes `c`, a click with `a` ends up with `c`. ### Split one value between several A transformation can have more than one **To Value**. Each click with the **From Value** then gets one of them, picked at random by **Weight**. Use it to test two sub IDs against each other, or to send only part of the traffic under a new value. 1. In **Create Transformation**, enter the **From Value** and the first **To Value**. 2. Click **Add another To Value** and enter the next one. 3. Set a **Weight** for each. **Share** shows the part of the clicks each one gets. 4. Click **Create**. ![The Create Transformation form with the From Value 1048211 split between the To Values zone-a at weight 70 and zone-b at weight 30, shown as 70% and 30%](/images/docs/custom-tokens-transformation-split.jpg "70% of clicks get zone-a and 30% get zone-b") To keep the original value for part of the traffic, add the **From Value** itself as one of the **To Values**. For example, `1048211` at weight 30 and `zone-a` at weight 70 leaves 30% of clicks unchanged. --- ## Use the token Put `{custom_token}`, `{custom_token2}`, or `{custom_token3}` in an Offer URL, a lander URL, or a traffic source's postback URL. Proferex replaces it with the click's value. For example, this Offer URL sends the click ID in `aff_sub` and the custom token in `aff_sub2`: ``` https://trk.rewardhubs.com/c?offer_id=4821&aff_id=10937&aff_sub={clickid}&aff_sub2={custom_token} ``` See [Sub ID](/docs/tracker/offers/index.md#sub-id). --- ## Add custom tokens to many campaigns - In the campaign form, **More → Custom Tokens** lets you add definitions while you create or edit a campaign. - The upload icon on the **Token Definitions** card adds many definitions at once, typed in or from a CSV file. - **Tracker → Custom Tokens** lists every definition across all your campaigns. Tick several to edit or delete them together. To copy a definition within a campaign, click its duplicate icon. --- ## See how each value performs The **Custom Tokens Performance** card on the campaign's **Custom Tokens** tab shows the visits, clicks, conversions, and revenue for each value. Pick which tokens to show in **Tokens**. To compare values across campaigns, go to **Tracker → Analytics** and group by **Custom Token 1**, **2**, or **3**. See [Analytics](/docs/reports/drill-downs/index.md). --- ## Next step Add `{custom_token}` to your Offer URL, then open your campaign link once and check the value in the **Click/Conversion Log**. See [Tracker Settings](/docs/account/tracker-settings/index.md#clickconversion-log).