PostHog feature flags cost calculator

PostHog bills feature flags by the request on a sliding curve, so your bill tracks traffic rather than team size. Enter your monthly flag requests to estimate it, then see it against Featureflip's flat price.

This estimates the feature flags line only. PostHog is a bundle, and analytics, session replay, and surveys are metered separately.

PostHog Pay-as-you-go

$5,520

per year, estimated

Featureflip Pro

$948

per year, flat. No usage-based fees on feature flag requests.

At this usage, PostHog Pay-as-you-go runs about $5,520/year, roughly $4,572/year more than Featureflip Pro at a flat $948. PostHog's bill climbs with your usage. Featureflip's changes only when you move to another plan.

PostHog rates sourced from posthog.com/feature-flags/pricing, checked October 8, 2026. Estimate covers Pay-as-you-go feature flag requests only; it excludes product analytics, session replay, surveys, and data warehouse (each metered on its own usage axis), paid platform add-ons (SSO/SAML enforcement, advanced permissions, audit controls), server-side local evaluation polling unless you add it to the input (each fetch of flag definitions counts as 10 requests, about 864,000 a month for one server polling every 30 seconds). Featureflip's side is the cheapest plan whose team-member and project limits fit these numbers.

The pricing behind the numbers

Sourced from posthog.com/pricing, checked October 8, 2026.

  • Free — $0, no credit card. Includes the first 1 million feature flag requests a month, plus separate free allowances on analytics, session replay, and surveys.
  • Pay-as-you-go — the same 1 million free, then usage-based per flag request: $0.0001 (1 to 2M), $0.000045 (2 to 10M), $0.000025 (10 to 50M), $0.00001 (above 50M). Each band charges only the volume inside it. Per-product billing limits are available.
  • Platform add-ons — SSO/SAML enforcement, advanced permissions, and audit controls are paid separately. Experiments are billed together with feature flags.

Two things this estimate deliberately leaves out. Every other PostHog product is metered on its own usage axis, so this is not a bundle price. And server-side local evaluation is not billed per flag check. PostHog bills the periodic fetch of flag definitions instead, at 10 flag requests each, which comes to about 864,000 requests a month for each always-on server instance at the default 30-second poll. That cost follows your instance count and poll interval, so add about 864,000 per instance to the input to include it. Per-request billing mainly affects client-side flags, where each browser session triggers a request.

Featureflip is flat, whatever your traffic

The Free plan costs nothing, Team is $49 per month ($39 a month, $468 a year, billed annually), Pro is $99 per month ($79 a month, $948 a year, billed annually), and Business is $249 per month ($199 a month, $2,388 a year, billed annually). Every plan runs unlimited evaluations, with no per-request or per-seat fees. See the full pricing page, or read the Featureflip vs PostHog comparison for the bundle-versus-focused trade-off and propagation differences.

Start free on Featureflip

Frequently asked questions

How much does PostHog charge for feature flags?
PostHog meters feature flags by the request. The first 1 million requests a month are free, then the rate is $0.0001 per request from 1 to 2 million, $0.000045 from 2 to 10 million, $0.000025 from 10 to 50 million, and $0.00001 above 50 million. Each band is charged only for the volume that falls inside it, so a 10-million request month costs about $460, not 10 million times a single rate. There is no seat cost and no subscription price for flags. Rates were checked on October 8, 2026 from posthog.com/pricing.
Does PostHog have a free tier for feature flags?
Yes, and it is a generous one: 1 million flag requests every month with no credit card, alongside separate free allowances on analytics, session replay, and surveys. For a side project or a pre-launch product that is often $0 for the whole stack. The meter only becomes a budgeting question once the product works and request volume climbs. Featureflip's Free plan is also free forever, with unlimited evaluations rather than a request allowance.
Do server-side feature flags cost less on PostHog?
Much less, and this is the single most important thing to understand before reading any estimate. PostHog server SDKs can evaluate flags locally against cached definitions, which is not billed per flag check. The periodic fetch of those definitions is billed, at 10 flag requests each. At the default 30-second poll, one always-on server instance uses about 864,000 requests a month, 86% of the free allowance (the Go SDK polls every 5 minutes, a tenth of that). So server-side cost scales with instance count and poll interval, whatever your traffic: two instances come to about 1.73 million requests, or $72.80 a month, and ten to about 8.64 million, or $398.80. Per-request billing primarily bites client-side flags, where every browser session triggers a request. If your flags are all server-side on a single instance, PostHog may well cost you nothing.
Why does my PostHog flag bill grow when my team does not?
Because the meter counts traffic, not headcount. Adding engineers costs nothing, but a successful launch that doubles your monthly active users roughly doubles your client-side flag requests and therefore your flag bill. That is the structural tension in usage-based pricing: the success case and the expensive case are the same event. A flat price decouples the two, which is what this calculator is showing you.
Does this estimate cover all of PostHog?
No, and deliberately so. This estimates the feature-flags line only. PostHog is a bundle, and product analytics, session replay, surveys, and data warehouse are each metered on their own separate usage axis, so adding them together would compare a whole product-data stack against a focused flag tool. Paid platform add-ons such as SSO/SAML enforcement, advanced permissions, and audit controls are also excluded. Experiments are billed together with feature flags. If you already want analytics from the same vendor, PostHog's bundled value is a genuine argument this calculator does not try to price.
How is this estimate calculated?
Your monthly flag requests are walked through PostHog's published bands, charging each band only for the volume inside it, and the monthly total is annualized. PostHog applies its volume discounts through those bands automatically and publishes no annual rate, so there is no billing toggle on its side. Featureflip's side picks the cheapest Featureflip plan that fits the team size you enter, flat regardless of traffic. Every rate is sourced and dated on this page.