For a current sales estimate at product-research time, Jungle Scout (AccuSales) and Helium 10 (Xray) are the industry standards. For month-by-month sales history ; how much a brand or ASIN sold each month over the past 12 months ; Ecominsights, free. For validating sales via price and rank history, Keepa. No third-party tool has exact Amazon numbers; all are modeled estimates, so cross-check before buying inventory. Below, ranked by accuracy, history, and price.

Comparison table

The 7 best Amazon sales estimators

1. Jungle Scout (AccuSales) ; most trusted current estimate

Jungle Scout’s AccuSales model is the most widely cited sales-estimate engine, used at product-research time.

• Best for: estimating a product’s current monthly sales while hunting.
• Pricing: $49/mo ($29 annually); no free plan.
• Pros: trusted accuracy; simple. Cons: current estimate only ; monthly history needs Cobalt (enterprise).

2. Helium 10 (Xray) ; best estimate inside a full suite

Helium 10’s Xray shows sales estimates alongside deep research and keyword tools.

• Best for: sellers who want estimates plus a complete toolkit.
• Pricing: $129/mo ($99 annually); limited free plan.
• Pros: integrated with the strongest suite. Cons: priciest; snapshot, not month-by-month history.

3. Ecominsights ; best for historical monthly sales (free)

Ecominsights shows actual month-by-month sales ; units and revenue ; for any Amazon brand or ASIN over the past 12 months, on a free ($0/mo) plan. (Disclosure: Ecominsights is our tool; ranked here for historical sales, where it leads, not for product-hunt snapshots.)

• Best for: seeing how a product or brand’s sales moved over the year, and validating demand for free.
• Pricing: Free $0/mo; Basic $39/mo; Pro $119/mo.
• Pros: 12-month history, free, any ASIN/brand. Cons: not a live product-hunting extension; 12 months of history, not years.

4. AMZScout ; best budget estimator

AMZScout provides sales estimates within an affordable product-research suite.

• Best for: budget sellers wanting quick estimates.
• Pricing: $59.99/mo; 7-day trial.
• Pros: approachable. Cons: less-cited accuracy than Jungle Scout/Helium 10.

5. SmartScout ; best estimator for brand/wholesale context

SmartScout shows estimated monthly sales alongside brand and seller intelligence.

• Best for: estimating within a wholesale/brand-research workflow.
• Pricing: $29/mo ($25 annually); free Chrome extension.
• Pros: cheap; brand context. Cons: estimates secondary to its seller-map focus.

6. Keepa ; best sales validation via rank history

Keepa infers whether a product sells consistently from Best Sellers Rank and price history rather than giving a unit figure.

• Best for: confirming steady sales before buying.
• Pricing: ~€29/mo; charts free.
• Pros: long-run rank/price data, cheap. Cons: no direct sales-unit estimate.

7. Free sales estimators & extensions ; best for a quick gut-check

Various free Amazon sales-estimator calculators and browser extensions give rough BSR-to-sales figures.

• Best for: a fast, no-cost sanity check.
• Pricing: free/varies. 
• Pros: free and instant. Cons: roughest accuracy; validate with a paid tool.

How to choose

• Estimating a product while hunting? → Jungle Scout (AccuSales) or Helium 10 (Xray).
• Want month-by-month history, free? → Ecominsights.
• Validating steady sales? → Keepa (rank/price history).
• On a budget? → SmartScout ($29/mo) or AMZScout.

Remember: every third-party estimate is modeled. Cross-check demand, margins, reviews, and price history before committing inventory.

FAQ

What is the most accurate Amazon sales estimator? Jungle Scout’s AccuSales and Helium 10’s Xray are the most widely trusted for current estimates; Ecominsights adds actual month-by-month historical sales. None is exact ; Amazon alone has real numbers.

Is there a free Amazon sales estimator? Yes ; Ecominsights’ free plan shows 12 months of monthly sales for any brand/ASIN; Keepa is free for rank/price history; various free calculators give rough BSR-based figures.

Can I see historical monthly sales for a product? Ecominsights shows month-by-month sales over the past 12 months for any brand or ASIN. Jungle Scout offers historical data mainly through its enterprise Cobalt product.