What will feature flags cost at your requests-per-month volume, and who is cheapest?

Enter your flag requests per month (in thousands) and growth rate. Get PostHog, Flagsmith and ConfigCat priced side by side, the 12-month spend, and the request volumes where the cheapest provider changes — before you build on one and find out when the invoice arrives.

Nothing is uploaded. Calculated in this browser from numbers you enter and approximate list prices you can edit. It cannot see your plan or your invoice.

1. Your flag usage

Thousands of flag requests per month today

Growth in volume per month (%)

Monthly budget in USD (optional)

Budget applies to

2. Comparison

Provider	Per month	Per year	12-month spend with growth

Where the cheapest provider changes

Thousand flag requests per month	Cheapest

Several providers are $0 at small sizes, so the first rows are ties. A free tier is not always enough: check seat caps, flag limits and environment limits at each vendor. Per-request pricing is simplest, but flat-fee plans (Flagsmith, ConfigCat) include a pool of requests you may already be paying for. Client-side SDKs that poll often can multiply request counts.

Rate cards (editable)

Provider	Free up to (K req/mo)	First paid plan (USD/mo)	K req in first plan	Overage per K req

Plans beyond the first stay at the defaults here; use the CLI --prices file to edit every plan. Press Compare after changing a value.

Prefer a CLI, or want a budget gate in CI?

node cli.mjs compare --kreq 300 --growth 6
node cli.mjs compare --kreq 800 --provider posthog --budget 300   # exit 1 over budget
node cli.mjs crossover
node cli.mjs compare --kreq 300 --prices prices.json --json

Get cli.mjs and engine.mjs — Node 18+, nothing to install, no network call. More: how to choose a feature-flag tool.

Common questions

Does this read my feature-flag account?

No. It uses only the monthly flag-evaluation volume (thousands of requests) you type and rate cards you can edit. It cannot see your plan, seat count, contract or invoice. Treat every figure as a way to compare options, never as what you will be charged.

Where do the prices come from?

They are approximate public list prices as best known in 2025, shown with an as-of line, and every number is editable. Vendors meter flags differently (requests, config downloads, seats, monthly active users) and change packaging often, so check each vendor's pricing page before deciding.

What is not included?

Longer seats, projects, experimentation and analytics add-ons, SSO, support plans and committed-use discounts. These are often the real bill, so use this to compare the per-request line, not to forecast the whole invoice. Targeting rules, SDK quality, self-hosting options and experimentation features are not priced here and often matter more than a few dollars.

Is my data uploaded anywhere?

No. The page calculates in your browser and sends nothing. The CLI reads local files and makes no network call.