ACOS, TACoS, ROAS & break-even calculator.
Four ratios, one set of numbers, because none of them means much alone. ACOS says what the advertised sales cost, and ROAS says the same thing inverted. Break-even ACOS says what they could have cost before they stopped paying. TACoS says whether the whole business is leaning on advertising. 28% is excellent against a 39% break-even and ruinous against a 15% one — so this compares them rather than reporting any one of them.
What the customer pays.
Landed cost of the unit.
Referral, closing and fulfilment — everything except advertising.
Only if you pay it separately from the fees above.
Total spend for the period you are judging.
Sales the ads were credited with. Drives ACOS.
Everything you sold, advertised or not. Drives TACoS.
28.75% vs 39.11%
10.36% of headroom before an advertised sale stops paying.
Healthy
Profitable with enough headroom to absorb a returned order or a bad week.
Is this campaign efficient?
Is the business leaning on ads?
How it is worked out.
ACOS = spend ÷ ad revenue · ROAS = ad revenue ÷ spend · TACoS = spend ÷ TOTAL revenue · Break-even ACOS = your contribution margin
- Ad Spend
- What the campaign cost over the period. Amazon's reports call it Spend, Flipkart calls it Ad Spend, Myntra calls it Total Spends — same number.
- Ad Revenue
- Sales the marketplace attributes to those ads inside the attribution window. This is not your total sales, and it is not what landed in your bank.
The attribution window matters more than sellers expect. Sponsored Products reports default to a 7-day window and Sponsored Brands to 14, so the same week of spend produces two different ACOS figures and neither one is wrong.
With real numbers.
One Sponsored Products campaign, last 30 days.
| Ad spend | ₹18,400 |
|---|---|
| Ad revenue (attributed sales) | ₹64,000 |
| Total revenue for the month | ₹2,30,000 |
| Unit: price / cost / fees / shipping | ₹1,299 / ₹420 / ₹286 / ₹85 |
| ACOS | 28.75% |
| Break-even ACOS | 39.11% |
| TACoS | 8.00% |
| ROAS | 3.48× |
18,400 ÷ 64,000 × 100 = 28.75% ACOS
Every ₹100 of sales the ads produced cost ₹28.75 in advertising. On the ₹1,299 unit below — ₹420 of product, ₹286 of fees, ₹85 of shipping — break-even ACOS is 39.11%, so there are 10.36 points of headroom before an advertised sale stops paying. TACoS on the same period is 8.00%: advertising produced ₹64,000 of a ₹2,30,000 month, so most of the business is still arriving without it. Read together those three say ‘efficient, with room, and not dependent’. Any one of them alone says almost nothing.
What the number means.
There is no universal good ACOS, and every published benchmark is describing somebody else's margin. The only honest yardstick is your own break-even ACOS — the share of the selling price left after product cost, marketplace fees and shipping.
| Range | Verdict | What it means |
|---|---|---|
| Under 20% | Room to spend | Comfortably profitable, and usually a sign bids are too low. The tell is impression share well below what the budget could buy — you are winning the cheap auctions and skipping the rest. |
| 20% – 31% | Healthy | Roughly half to eighty per cent of break-even. Profitable with enough headroom to survive a bad week or a returned order. |
| 31% – 39% | Thin | Still profitable, barely. Reasonable on a launch or a defensive campaign; not a resting state for your best seller. |
| Over 39% | Losing money on ad sales | Each advertised sale costs more than it contributes. That is a legitimate choice when you are buying rank, reviews or shelf space — it is only a problem when nobody chose it. |
One thing ACOS can never tell you: whether the advertising grew the business or simply took credit for sales that would have happened anyway. That question belongs to TACoS.
Where this goes wrong.
- 01
Comparing ACOS across products with different margins
A 30% ACOS on a ₹1,299 unit at 39% margin is healthy. The same 30% on a ₹299 accessory at 18% margin loses money on every click. Sorting a campaign list by ACOS puts the low-margin loser near the top.
- 02
Reading ACOS as total advertising efficiency
ACOS only sees the sales the ads claimed. It cannot see organic sales the advertising caused, and it cannot see the organic sales you would have made regardless. Both live in TACoS.
- 03
Chasing a lower ACOS by cutting spend
Pause everything except branded keywords and your ACOS will look superb while the business shrinks. Branded search converts at rates no other traffic reaches, so an account that is mostly branded has a flattering ACOS and no growth engine.
- 04
Comparing a 7-day report against a 14-day one
Sales attributed over fourteen days make ACOS look better than the same sales attributed over seven. Compare like with like or the trend line is fiction.
- 05
Judging a campaign on its first week
Spend lands immediately; attributed sales keep arriving for days afterwards. Every new campaign's opening ACOS is worse than the one it will settle at.
The rest of the set.
Where the real numbers live.
- SP Search Term Report
Upload the export and see which specific search terms spent without converting. That is where ACOS is actually made — not in the bid slider.
- Amazon PPC Audit
A full audit from one search-term file: wasted spend, harvest candidates, and the campaigns worth more budget.
- Amazon Settlement Calculator
Fees are half of your break-even ACOS. Work out the real payout per order before you decide what ACOS you can afford.
Your ACOS is a symptom. The search-term report is the cause.
This calculator tells you what your ACOS is. The Search Term module tells you which terms produced it — every query that spent money, whether it converted, and what negating it would have saved. Upload the export you already have.
Questions people actually ask.
What is a good ACOS on Amazon?
The one comfortably below your break-even ACOS. Break-even ACOS is your contribution margin — selling price minus product cost, marketplace fees and shipping, as a share of selling price. If that is 39%, an ACOS in the twenties is healthy and 45% is losing money on every advertised sale. Any figure quoted as an industry average is describing someone else's cost structure.
What is the difference between ACOS and TACoS?
ACOS divides ad spend by the sales the ads were credited with. TACoS divides the same spend by your total sales, organic included. ACOS tells you whether a campaign works; TACoS tells you whether advertising is carrying the business. TACoS is always the lower of the two unless every sale you make comes from an ad.
How do I convert ACOS to ROAS?
They are reciprocals: ROAS = 100 ÷ ACOS. A 25% ACOS is a 4× ROAS; 50% is 2×. Neither number carries information the other lacks — Amazon reports ACOS, most agencies quote ROAS, and sellers get asked for both.
Is a high ACOS ever acceptable?
Yes, when you are buying something other than today's profit: sales velocity for a launch that needs to rank, defence of a keyword a competitor has started bidding on, or clearance before a long-term storage fee lands. What is not acceptable is a high ACOS nobody decided on.
Why does my ACOS differ from the figure in Seller Central?
Almost always the date range or the attribution window. The campaign manager's default lookback differs from the downloadable reports, and attributed sales keep arriving for up to fourteen days after the spend. Re-pull an old period and the ACOS will have improved on its own.
How do I actually reduce ACOS?
By finding the specific search terms that spend without converting, rather than lowering every bid. On a typical search-term export a small number of terms carry most of the wasted spend, and negating those moves ACOS without costing you volume.