ROAS / MER Calculator
Compute ROAS (per channel), MER (blended), break-even ROAS by margin, and target spend. The post-iOS 14.5 marketing-math standard. Free.
ROAS / MER Calculator
ROAS measures channel-level efficiency (attributed revenue ÷ ad spend). MER (Marketing Efficiency Ratio) measures blended efficiency (total revenue ÷ total marketing). After iOS 14.5 broke per-channel attribution, MER became the trusted top-line metric for most DTC + SaaS marketers. The tool computes both, plus break-even ROAS at your gross margin.
How to Use the ROAS / MER Calculator
Pull attributed revenue + spend per channel
From Meta Ads Manager, Google Ads, TikTok Ads — each platform's reported "purchase value." Since iOS 14.5 (April 2021) these are partly modelled rather than observed, so don't treat them as ground truth.
Pull total revenue + total marketing
From your ERP / Shopify / Stripe for revenue. From your finance system for marketing — include all paid channels, agency fees, retainer creative, influencer payments. Use the same period.
Enter your gross margin %
Net of COGS, shipping, payment processing. Most consumer brands run 40-65%; SaaS 70-90%; commodity retail 20-30%. This determines your break-even ROAS — the ROAS below which you actually lose money on each marketing dollar.
Read MER first, then channel ROAS
MER is the trustworthy top-line. Channel ROAS is platform-reported and post-iOS-14.5 noisy. If MER is healthy but a single channel's ROAS looks scary low, the channel may still be working — its attribution is just broken. Cut spend only if both MER and the channel ROAS drop in tandem.
ROAS vs MER vs POAS — The Post-iOS 14.5 Marketing-Math Stack
Why MER Replaced ROAS as the Top-Line Metric
Pre-iOS 14.5 (April 2021), channel-attributed ROAS was the gold standard for paid media optimisation. Meta and Google's pixel-based attribution was accurate enough that "Facebook says we made USD 4 for every USD 1 spent" was a meaningful claim. Apple's App Tracking Transparency framework broke that — from iOS 14.5 an app must ask permission before tracking a user across apps, and Flurry Analytics measured opt-in at just 4–6% of US users and 11–15% worldwide in the weeks after launch. Platform-reported revenue for iOS traffic became partly modelled rather than observed, and channel ROAS lost its claim to be ground truth.
MER (Marketing Efficiency Ratio) — total revenue ÷ total marketing spend, with no attempt at per-channel attribution — emerged as the trusted top-line metric because it's based on actual revenue (not platform-reported attributed revenue) and actual total marketing spend (which you control). MER doesn't tell you which channel drove the revenue, but it tells you the truth about whether marketing in aggregate is paying off. Most modern DTC + SaaS brands now lead with MER on their marketing dashboards, with channel ROAS as a secondary directional metric.
Break-Even ROAS — The Math That Most Marketers Skip
Break-even ROAS = 1 ÷ gross margin. At 50% gross margin, break-even ROAS is 2× — every dollar of ad spend needs to generate USD 2 of revenue just to cover the variable cost of the goods sold. At 25% margin (typical e-commerce after platform fees), break-even is 4×. At 75% margin (SaaS), break-even is 1.33×. Channel reports often show ROAS of "2.5×" or "3×" as wins, but if your gross margin is 30%, that's barely covering COGS and contributing zero toward overhead, salaries, or profit. Most "winning" Meta campaigns at 2-3× ROAS are actually losing money for consumer brands after the full P&L.
POAS (Profit On Ad Spend) = ROAS × gross margin. This is the more useful single number — it tells you actual dollar profit per ad dollar. POAS of 1.0× = break-even (you got back exactly what you spent). POAS above 1.0× = the channel covers its cost of goods and contributes to overhead; below 1.0× = losing money on every ad dollar regardless of how impressive ROAS looks. Brands that bid on profit rather than revenue feed margin-adjusted conversion values into their ad platforms so that the platform's target-ROAS bidding optimises for profit.
"A 3× ROAS sounds great. At 30% gross margin, break-even ROAS is 3.33×, so 3× is losing money on every ad dollar. The ROAS dashboards make this invisible. POAS = ROAS × Margin. That single multiplication exposes whether marketing is making or burning money."
What a "healthy" MER looks like
There is no published benchmark — MER depends on your gross margin and on how much of your revenue you are prepared to spend acquiring it. The arithmetic is the guide: MER must clear 1 ÷ gross margin for marketing to cover cost of goods, and clear it by enough to fund overhead and profit. A brand deliberately buying growth can run MER close to break-even for a period; a mature brand living mostly on organic and repeat purchases will run a much higher one. Benchmark against your own margin structure and prior periods, not against other companies' dashboards.
The MER Trap At Scale
MER quietly hides the channel mix problem at scale. A brand that doubles spend and watches MER hold steady looks healthy — but if 80% of the spend lift went into a single channel with declining incremental return, the next doubling will break the model. The defence is to track MER alongside individual channel ROAS trend lines and a periodic incrementality check (geo-holdout test once or twice a year). If MER is stable but the channel that drives most spend is showing declining ROAS, you're in the slow-build-up to a marketing crisis even though the top-line metric looks fine. Use MER as the headline; never use it alone.
Break-even ROAS is one over your gross margin
ROAS = Revenue ÷ Ad Spend (per channel). MER = Total Revenue ÷ Total Marketing (blended).
iOS 14.5 (April 2021) made cross-app tracking opt-in; Flurry measured US opt-in at 4–6% and worldwide at 11–15% in May 2021.
Post-ATT, platform-reported iOS conversions are partly modelled, not observed — which is why MER, built on your own revenue ledger, took over as the top-line.
Break-even ROAS = 1 ÷ Gross Margin. At 50% margin, you need 2× ROAS to break even.
POAS = ROAS × Margin. Exposes whether ads make or burn money.
Profit bidding = feeding margin-adjusted conversion values into a platform's target-ROAS bidding, so it optimises for profit rather than revenue.
Marketing as % of revenue = 1 ÷ MER. A MER of 4× means one dollar in four of revenue goes to marketing.
Channel gross profit = attributed revenue × gross margin − ad spend. It is the dollar version of POAS − 1.
Triple Whale, Rockerbox, Northbeam emerged 2021-2023 to fix post-ATT attribution.
iROAS (incremental ROAS) measured via geo-holdout tests is the rigorous-attribution gold standard.
Frequently Asked Questions
- ROAS measures a single channel's attribution-reported revenue against its spend. MER (Marketing Efficiency Ratio) measures total business revenue against total marketing spend — no attribution, no channel-level attribution at all. Post-iOS 14.5, MER is the more trustworthy top-line because it doesn't rely on platform attribution that's now meaningfully broken. ROAS is still useful for relative channel comparison but should not be treated as ground truth.
- Post-ATT (Apple App Tracking Transparency), Meta cannot observe most iOS conversions and fills the gap with modelled estimates, so Meta-reported ROAS and your ledger will disagree. If your true MER is 4× and Meta shows 2× ROAS, the channel may be performing better than its dashboard says — Meta just can't see most of the conversions. The fix: trust MER for top-line, use Meta ROAS as a relative-trend metric (is it going up or down) rather than an absolute claim.
- Break-even ROAS = 1 ÷ Gross Margin. It's the ROAS below which you lose money on every ad dollar even before counting overhead. At 50% margin, you need 2× ROAS to recover your COGS. At 30% margin, you need 3.33×. At 75% margin (typical SaaS), you need 1.33×. Most marketers don't compute this and end up celebrating "winning" 2-3× ROAS campaigns that are actually losing money for low-margin businesses.
- POAS (Profit On Ad Spend) = ROAS × Gross Margin. It tells you actual dollar profit per ad dollar after COGS. POAS > 1 means profitable; POAS < 1 means losing money. Yes — it's strictly more useful than ROAS because it bakes in the margin reality. The challenge: it requires you to feed product-level margin data into your ad platform (Google Ads supports this; Meta doesn't natively). For most brands, POAS-aware ROAS reporting in spreadsheets / BI tools is the practical compromise.
- Start from your gross margin: MER must exceed 1 ÷ gross margin for marketing to cover cost of goods, and exceed it by enough to fund overhead and profit. A brand deliberately buying growth may run MER near that break-even for a period, planning to recover on repeat orders; a mature brand living on organic and retention will run far above it. If MER is below your break-even, marketing is destroying value at the business level — investigate immediately. If MER is very high and growth has stalled, you may be under-investing in marketing.
- Yes — total marketing spend means total. Include media spend, agency retainers, creative production, influencer payments, sponsored content, affiliate commissions, marketing tools (Klaviyo, Triple Whale, etc.). Exclude only true overhead (the CMO's salary, marketing intern). The cleanest definition: anything that scales up if you grow marketing investment. Most brands' "marketing spend" reported to their CFO is 1.5-2× the media-only number — make sure MER is computed on the full figure.
- They blend platform-reported attribution with first-party data, post-purchase "How did you hear about us?" surveys, and probabilistic modelling to estimate true channel contribution. Northbeam, Rockerbox, Triple Whale and Polar compete in this space. Helpful for medium-large brands and priced accordingly; for smaller spenders, MER alone is usually sufficient.
- iROAS measures the lift from ads vs a holdout group that didn't see ads. The gold standard: geo-experiments (run ads in 5 states, hold out 5 similar states, measure revenue difference). Meta, Google, and TikTok all offer "conversion lift" studies that approximate this. iROAS is the only rigorously-attributed ROAS — but it's expensive (requires holdout that doesn't see ads), slow (takes 4-8 weeks), and only feasible for large spenders. For most brands, MER + directional channel ROAS is the practical compromise.
- Lead with MER. Most CFOs and CEOs find "total revenue ÷ total marketing" intuitive and trust it because the inputs are unambiguous. Add POAS as the profit-side companion (revenue is good; profit is better). Channel ROAS is for your internal optimisation conversations, not stakeholder reports — too easy to misinterpret post-iOS-14.5. The standard pattern: dashboard MER and POAS at the top; channel ROAS as second-row optimisation detail.
- US ad CPMs are far higher than ASEAN domestic rates, but US order values usually are too — the math can work if your COGS is ASEAN-priced and revenue is in USD. Watch out for cross-border fulfilment cost and for customs duties and tariffs, which have moved sharply since 2025. Run MER with all-in landed COGS, not factory cost; this catches the hidden international-fulfilment drag that local-only competitors don't face. The iOS 14.5 attribution gap is identical in any market; the MER-first framework applies.
Related News
You may be interested in these recent stories from our newsroom.
-
DeepSeek Hired Bankers. That Is Not the Same as Filing to List.
Four underwriters for a STAR Market float, a pre-IPO round near $74.5bn, and no prospectus. The reports do not agree on whether the listing...
-
Forus Raised Less Money at Three Times the Price, Four Months Later
A $150m Series C at $3bn follows a $160m Series B at about $1bn in May. The founders sold roughly five per cent instead of sixteen.
-
Mistral Raised €3 Billion. The Gigawatt by 2030 Is Not Funded Yet.
Mistral's Series D is led by Samsung at a valuation above €21 billion, nearly double last year's. The money is for compute, and TCS committe...
Method & sources
How it computes
ROAS = channel attributed revenue ÷ channel paid spend; MER = total revenue ÷ total marketing spend; break-even ROAS = 1 ÷ gross margin; POAS = ROAS × gross margin; marketing as % of revenue = total marketing ÷ total revenue; channel gross profit = attributed revenue × gross margin − paid spend. Verdict compares ROAS with break-even and 1.5 × break-even.
What this tool implements
- Definitional ratios only — no attribution modelling, no benchmarks asserted
- Break-even derived from gross margin (covers cost of goods only; overhead not included)
- Apple App Tracking Transparency (iOS 14.5, April 2021) cited as the reason platform-reported ROAS is partly modelled; Flurry opt-in measurements cited with date
Sources
What can make this go out of date
- none at runtime
Pick up where you left off
Stored only in this browser — never sent to our servers.