Credits and Limits

1stUnit uses Runway as its generation provider. Every run consumes credits from your Runway account. This page explains how the balance is shown, how the cost estimate is computed, and what limits Runway enforces on the API.

Where the balance shows up

Your live Runway credit balance appears in two places in 1stUnit:

  • At the bottom of the pipeline board, in the stats row, shown in amber as Balance: N credits.
  • In the Launch bar at the bottom of the New Run form.

Both numbers are fetched live from Runway each time you open the surface. If 1stUnit cannot reach Runway (no internet, invalid API key), the balance shows a dash instead of a number.

A close-up of the pipeline board's stats row, with the amber credit balance prominent.

Estimated cost per run

The New Run form shows an Estimated credits number next to the Takes field. It updates as you change the model, duration, takes, or resolution.

The estimate is a local calculation, intended as a general guide. Runway does not return an exact cost up front, and rates can change over time. Your account will be charged the actual Runway rate when the run completes — see Runway's pricing page for current per-model rates.

In general, image models are priced per image (with higher resolutions costing more), and video models are priced per second of output (with higher resolutions and audio adding to the rate). Total cost for a run is the per-generation rate multiplied by the number of takes.

API limits

Runway organizes API usage into tiers that determine how many generations you can run concurrently and how many you can run per day. New accounts start at the lowest tier and are upgraded automatically as you spend more on the platform. See Runway's tiers documentation for the current thresholds.

Two limits in particular affect how 1stUnit behaves:

  • Concurrency. If you launch more runs than your tier allows to run simultaneously, Runway places the extras in a server-side queue ("throttled") and starts each one as a previous run finishes.
  • Daily generations. A rolling 24-hour cap on the number of generation requests. If you exceed it, Runway returns an error and the run appears as failed in the Node graph.

1stUnit does not block you from queueing more than these limits allow — it lets Runway enforce them and reports back what happens.

Throttled vs failed

While a run is queued behind another one, 1stUnit shows it as queued, waiting for previous run on the placeholder card. This is not an error. It just means Runway is holding your request in line. As soon as the previous run completes on Runway's side, the throttled run moves to running and starts producing.

A failure, by contrast, shows up in the Node graph with a red dotted border and the error message inside. Common causes are content policy blocks, invalid input combinations, or the daily limit being hit.

How the API key is stored

Your Runway API key is stored in 1stUnit's local settings database. It never leaves your PC except when 1stUnit sends it directly to Runway as part of an API call. It is not included in any export, not synced to a cloud service, and not embedded in the app build.

If you ever need to rotate the key (for example after a Runway account change), open Edit > Preferences, paste the new key, and save. The change takes effect on the next run.

Topping up your balance

Credit purchases happen on Runway's website, not in 1stUnit. Sign in to your Runway developer account and add API credits there (note this is NOT the Web UI credits for the regular account). The new balance will show up in 1stUnit the next time you open the pipeline board or the New Run form.

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