Accounts & billing

Brainstorm works with no account at all — bring your own model key and everything runs locally. An account adds hosted models you pay for from a balance (no key wrangling); a Plus subscription adds cloud-synced, collaborative boards on top.

Everything lives under the hamburger menu (top-left), which has four tabs: Boards, Account, Models, and Usage.

The Account tab showing the signed-in state, balance pill, and per-track BYOK-vs-hosted controls for Chat and Image generation — The Account tab: sign-in state and balance. Per-track BYOK-or-hosted model settings now live in the Models tab.

Creating an account

In the Account tab, sign up with email and password or Google. Email sign-ups get a verification link; verifying your address unlocks paid actions and adds a $1 welcome credit to get you started.

You can keep using Brainstorm signed out — you just won’t have hosted models, cloud sync, or collaboration.

Two ways to use a model: BYOK or hosted

The choice is per feature — you can bring your own key for chat while paying for hosted image generation, or any mix. In the Models tab, each track (Chat and Image generation) offers:

My own key (BYOK) — point it at any OpenAI-compatible endpoint with your own API key. This is free — requests run from your browser and never touch our balance. See Chat & LLM for the fields.
Hosted — pick a model from a curated list and we call the provider for you. Each request is metered against your dollar balance at the model’s listed price. No keys to manage.

The Models tab with the Chat and Image generation tracks, each toggled between My own key and Hosted — showing the BYOK model / base URL / API key fields and the hosted model picker — The Models tab: per-track BYOK-or-hosted controls for Chat and Image generation.

Balance and top-ups

Your balance is a single dollar amount that funds all hosted usage (chat and image generation draw from the same pool). A balance pill shows the current total.

Top up any amount (from $1) via Stripe Checkout from the Account tab. Top-up balance never expires. Stripe handles payment and tax and emails you a receipt and a VAT invoice (PDF) right after you pay — nothing to chase down.

Plus subscription

Plus is $15/month and adds:

$15 of usage credit every month — your balance is refilled to $15 of subscription credit each billing cycle (it’s a cap, not a running total: unused credit doesn’t roll over). Hosted usage spends this subscription credit first, then any top-up balance.
Cloud sync — your boards back up to the cloud and sync across your devices. Without Plus, boards are saved locally only.
Collaboration — invite people to share and edit boards together. See Collaboration.

Subscribe (and later Manage subscription — update your card or cancel) from the Account tab; both open Stripe’s hosted pages. Stripe emails you a receipt and VAT invoice for every charge, so there’s nothing to view in-app. There’s no free trial, and it’s a single flat plan.

Cloud sync is a Plus feature — free accounts (and signed-out use) keep their boards local to the device. Plus adds both cross-device sync of your own boards and collaboration on shared ones.

If a subscription lapses, your local boards keep working and cloud boards stay readable and downloadable for a retention window; sync just stops pushing new changes until you resubscribe.

Usage

The Usage tab lists your metered hosted requests — per model, with token counts and what each one cost — so you can see where the balance goes. Pick a date range to scope the report, and each row shows the model, its request and token (or image) counts, and the amount charged, with a total at the bottom. BYOK requests don’t appear here (they never touch our servers).