Can I cancel anytime?

Yes. Cancel your subscription at any time from billing settings. No lock-in contracts, no cancellation fees.

What happens after the trial?

After your 14-day trial, access continues only if billing is added before the trial ends. You can add or update billing anytime from your account settings — no lock-in contracts.

Do I need a card to start?

No. You can run the free tools without an account, and paid trials start without a card. Add billing before day 15 only if you want paid access to continue after the trial.

Is there a free trial?

Yes. Starter and Pro both start with a full 14-day free trial. Stripe checkout starts the trial without a card. Add billing before day 15 to keep access; if you do not, trial access ends instead of billing automatically. The Free plan still includes: One free run per tool per day, no account needed.

What payment methods do you accept?

Payments are processed by Stripe, which holds PCI DSS Level 1 certification as the payment processor. We accept all major credit and debit cards. Enterprise plans are handled directly — contact us for details.

Yes. Upgrade or downgrade at any time. Changes take effect immediately, and we prorate billing automatically.

Yes. Your tool inputs and workspace data stay isolated to your account or browser session. We do not sell your data, and we do not use private customer data to train public foundation models.

Yes. All data is encrypted at rest and in transit. Your data stays isolated and never trains public AI models. See our Security page for details.

Do you train public models on my data?

No. Your workspace data is isolated for your operational workflows and is not used to train public models.

Pricing

One brain for your company's decisions.

Run every tool free. Pro is $99 USD/month when you need saved Decision Memos, exports, AI help (Beta), handoffs, and API keys. Start with a 14-day free trial.

No card to start. No charge until day 15; cancel anytime. If billing is not added before the trial ends, access ends instead of auto-billing.

All prices shown in USD

Free

Run every decision tool across 12 industries on your numbers. No account or card.

$0USD

Try the tools on one live decision before you make an account.

Start Free

Every structured decision tool across 12 industries — real outputs, full decision trails
Run in your browser; results stay in this session (no account needed)

See all included details

One free run per tool per day, no account needed.
CSV export and saved runs start on Starter; JSON export and tool chaining start on Pro

BrainStack Studio Starter

Essential tools for growing businesses

$29USD/mo

14-day trial. No card to start. $29 USD/mo after trial.

Save runs and export CSV when you need a light decision record.

Trial and billing details

No card to start.

Everything in Free, plus:
Run every decision tool as often as needed
CSV export of calculator results

See all included details

Save your tool runs to your account (reopen with assumptions intact)
One AI-assisted rewrite per day: turn a dense result into a plain memo (Beta, provider-dependent)
Monitored email support

BrainStack Studio Pro

$99USD/mo

14-day trial. No card to start. $99 USD/mo after trial.

Best for most: $99 USD/mo unlocks saved Decision Memos, exports, AI rewrites (Beta), tool handoffs, and API keys.

Trial and billing details

No card to start. Pro is $99 USD/mo after trial.

Everything in Starter, plus:
Unlimited AI-assisted rewrites: convert any result into a shareable memo, any time (Beta, provider-dependent)
JSON export and printable PDF reports — board-ready, audit-ready

See all included details

Save unlimited runs across every device: reopen any past scenario exactly as you left it
Tool-to-tool result handoffs: send ROI savings directly into a cash-flow model without retyping a number
API key management: 100 authenticated requests per minute with per-key usage tracking
Draft operating-plan builder: describe a workflow, get draft modules, runbooks, and proof gates
Unlimited content drafts from tool outputs with CSV and JSON export formats (Beta, provider-dependent)
Expedited email triage: your support requests go to the front of the queue

Monthly limits

Free, Starter, and Pro at a glance

Free

One free run per tool per day
No account or card required for the first run
Browser-only result unless you sign up to save it

Starter

$29/mo

Unlimited decision-tool runs
Saved run history and CSV export
One AI-assisted rewrite per day and 3 content drafts per day

Pro

$99/mo

Everything in Starter
Unlimited AI-assisted rewrites and content drafts while providers are available
JSON export, printable reports, tool handoffs, and API keys at 100 requests/min

Billing terms

14-day no-card trial

Starter is $29 USD/mo after trial.
Pro is $99 USD/mo after trial, or $990 USD/yr on annual billing.
No card to start. No charge until day 15; cancel anytime.
If billing is not added before the trial ends, paid access ends instead of auto-billing.

What happens after I start Pro?

Quickest path to Pro

Start a free trial, run your first scenario, then decide.

Start Pro Trial Explore tools free

For

Founder, operator, or finance lead with a live business question

Output

A structured decision memo with assumptions, scenario notes, and next steps

Controls

Full 14-day trial access. No card to start.

Security and proof notes

How We Earn Trust

Every figure on the /proof page was computed seconds ago by the same engines that power these tools. Re-run any of them with your own inputs and get the identical result.

Deterministic, auditable math

Every result is a pure function of your inputs. Same numbers in, same answer out — re-run it next quarter and reproduce it exactly. No hidden randomness, no model drift.

See it run live →

Published formulas, standard citations

NPV, payback, break-even, and contribution margin use textbook definitions — cited to Brealey, Myers & Allen and Horngren. Check the math against any finance reference. That is the point.

Human review gates, not blind automation

Every run shows inputs, assumptions, and decision trail — attached for a teammate to review before any action. These tools never send emails, change policies, or move money on their own.

decision tools

Public and paid tool surfaces render from the tool registry.

Source: TOOLS registry

industry paths

Explorer routing covers these configured operating contexts.

Source: INDUSTRIES explorer registry

workflow examples

Solution pages render from the workflow example registry.

Source: SOLUTIONS registry

Encrypted at RestAudit Trail on Every ActionCancel AnytimeNo Lock-in Contracts

Compare every plan detailOpen the full feature table when you need the fine print.

Capability	free	starter	pro
Saved workLive Example: reopen last month's cash-flow run with its assumptions intact.	Stored only in this browser	Save tool runs to your account (Explorer sessions up to 10)	Save unlimited runs across devices
Calculator runsLive Example: run a break-even check, then rerun it with a higher labor cost.	One free run per tool per day, no account needed.	Run every decision tool as often as needed	Run every decision tool as often as needed
Exports and reportsLive Example: send a CSV result to a spreadsheet or print a memo for a meeting.	View results in browser only	CSV export for calculator results	JSON exports and printable reports
Reuse numbers between toolsLive Example: send ROI savings into a cash-flow forecast without retyping.	Share links with prefilled inputs	Share links with prefilled inputs	Pass results between calculators (ROI, Cash Flow, Break-Even, Pricing)
AI-assisted rewriteBeta Example: take a 300-line ROI output and turn it into a 5-sentence owner memo.	Not included — core calculators still run fully	One AI rewrite per day (provider-dependent)	Unlimited AI rewrites while providers are available
Content drafts from resultsBeta Example: draft a follow-up email from a completed cash-flow forecast.	Not included — use the result as your writing source manually	Up to 3 drafts per day from tool results (provider-dependent)	Unlimited drafts with CSV and JSON export formats (provider-dependent)
Draft operating plansLive Example: describe a client-onboarding workflow and get a draft with steps, owners, and checkpoints.	Sample plan only — no custom workflows	Sample plan only — no custom workflows	Create custom draft plans: describe the workflow, get draft modules, runbooks, and proof gates
API keysLive Example: let an internal script call a tool with a tracked API key.	Use the web app only	Use the web app only	100 authenticated requests/min, API keys, and usage tracking
Help and rolloutLive Example: ask support to help unblock checkout, exports, or account access.	Community docs	Monitored email support	Expedited email triage
Security controlsReview Example: confirm who can access saved work and API-key usage logs.	Standard encryption	Standard encryption plus account history	API key controls, account history, and key usage telemetry

Frequently Asked Questions

Need one last check before choosing?

Ready to build your first Decision Memo?

Start your 14-day free trial. No card to start. No charge until day 15; cancel anytime. If billing is not added before the trial ends, access ends instead of auto-billing. Your first run produces a Decision Memo with assumptions, scenarios, and approval trace.

One brain for your company's decisions.

Free

BrainStack Studio Starter

BrainStack Studio Pro

Free, Starter, and Pro at a glance

Free

Starter

Pro

14-day no-card trial

Start a free trial, run your first scenario, then decide.

The math is the proof.

Deterministic, auditable math

Published formulas, standard citations

Human review gates, not blind automation

Plan Comparison

Frequently Asked Questions

Ready to build your first Decision Memo?