Facebook / Meta Ads Budget Calculator with iOS 14 reality

Meta auctions on impressions, so the math chain is: CPC = CPM ÷ (CTR × 10), CPL = CPC ÷ Conversion rate, Monthly budget = Target leads × CPL. Reverse it to forecast: Expected leads = Budget × CTR × Conversion rate ÷ (CPM ÷ 1,000). Both directions are wrapped into this calculator — pick a mode, the formula runs in the right direction.

Spend up to your maximum acceptable CAC, not a fixed number. Calculate it: take your customer LTV (or first-purchase profit if you can't measure LTV yet), decide the % you'll allocate to growth, and that's your max CAC. Back-solve max CPL, max CPC, and required spend. A typical B2B account with 200 lead-form fills per month at €15 CPL = €3,000/mo; that's the floor. Above the floor you scale until CAC hits its ceiling — usually around 2–3× spend before efficiency degrades.

CPM €6–€18, CTR 0.9–1.5%, conversion rates depend heavily on objective: Instant Lead Forms convert at 30–50% (users never leave Meta), Conversions-to-LP at 5–10%, e-commerce 2–4%, traffic objective 3–5%. Lead forms feel cheap on CPL but the leads are usually 2–3× lower quality than LP leads — pair the budget calculator with a close-rate input to see the real CAC.

Lead Forms have higher CVR (low friction, mobile-native, autofill from Meta profile) but lower lead quality (frictionless = unqualified). Landing pages have lower CVR but higher quality (people who fill in the form actually want what you're selling). Run this calculator twice: once with Lead Form defaults, once with Conversions defaults. Compare CPL × close rate = CAC. The higher-CAC channel by lead quality usually wins, even when the CPL looks worse.

Meta runs on daily budgets — divide your monthly figure by 30. Meta can spend up to 25% above a daily budget on a high-traffic day but evens out over time. For lifetime budgets (campaigns with a fixed end date), Meta optimizes more aggressively for early performance, which can backfire if your creative needs a few days to find its audience. Daily budgets are usually safer for steady-state campaigns; lifetime is better for promotions with deadlines.

Two reasons stack: (1) the calculator's CPM/CTR/CVR defaults are blended medians — your account's real numbers depend on creative quality, audience, and offer-market fit. New accounts often see CPM 30–50% higher in the first 60 days while the algorithm calibrates. (2) Tracking gaps. Meta misses 30–50% of conversions post-iOS 14, so reported CPL looks 50–100% higher than reality. The leads happened — Meta just didn't see them. Without Conversions API, both your reporting and your auto-bidder are blind.

Yes — Instagram is a placement inside Meta Ads Manager, not a separate platform. CPM and CTR shift slightly between Feed, Reels, and Stories (Reels usually has cheapest CPM but lowest CVR; Feed has highest CVR but priciest CPM), but the overall math is identical. If you're running placement-specific campaigns, run the calculator once per placement with that placement's CPM and CTR.