one-line definition
ROAS (Return on Ad Spend) measures how much revenue you earn for every dollar spent on advertising.
formula: ROAS = Revenue from ads ÷ Ad spend
tl;dr
A ROAS of 3x means $3 revenue per $1 spent. For SaaS with recurring revenue, factor in LTV not just first-month revenue — a 1x ROAS on first purchase might actually be 5x when you include 12 months of retention.
Simple definition
ROAS tells you how efficiently your ad spending turns into revenue. A ROAS of 5 means every $1 in ads produced $5 in revenue. For solo founders, ROAS is the go/no-go metric for paid channels — it answers whether your ads are making money or burning it. The catch is that ROAS can be misleading if you only count immediate revenue. For subscription products, the true ROAS unfolds over the customer's lifetime, so you need to pair it with your LTV estimates.
How to calculate it
ROAS = Revenue from ads / Ad spend. If you spent $600 on Facebook Ads last month and the customers acquired through those ads generated $2,100 in revenue, your ROAS is $2,100 / $600 = 3.5x. For SaaS, decide whether you are measuring first-month revenue or projected LTV. Example: you spend $500 on ads, acquire 10 customers at $19/month. First-month ROAS = $190 / $500 = 0.38x (looks terrible). But average retention is 8 months, so LTV-based ROAS = ($19 x 8 x 10) / $500 = $1,520 / $500 = 3.04x (profitable).
Example
You sell a $39/month analytics tool and run Google Ads targeting "simple website analytics for small business." In one month you spend $1,200 and acquire 15 paying customers. First-month revenue is 15 x $39 = $585, giving a first-month ROAS of 0.49x. Looks like you are losing money. But your average customer stays 10 months, so projected LTV is $390 per customer. Projected total revenue: 15 x $390 = $5,850. LTV-based ROAS = $5,850 / $1,200 = 4.88x. The campaign is highly profitable — you just need enough runway to absorb the upfront cost while revenue catches up. This is why ROAS without LTV context can kill a winning campaign too early.
Related reading
Related terms
- CPC
- CAC
- LTV
FAQ
What ROAS should I aim for as an solo founder?+
A 3x ROAS (or higher) is a common baseline for profitability after accounting for product costs. For subscription products, calculate ROAS using projected LTV, not just first-month revenue.
What is the difference between ROAS and ROI?+
ROAS measures revenue per ad dollar and ignores other costs. ROI factors in all costs (product, team, infrastructure). A 4x ROAS can still mean negative ROI if your margins are thin.