App ComparisonJun 16, 2026 · 7 min read

Shopify Inventory Forecasting Apps: Inventory Planner vs Cogsy vs Stocky

Inventory forecasting tools solve two expensive problems: stockouts (lost sales when a product sells out before reorder arrives) and overstock (capital tied up in slow- moving inventory). At low SKU counts, a spreadsheet handles this adequately. Above a certain complexity threshold, an automated forecasting tool saves more in inventory carrying costs than it charges in subscription fees.

When a Forecasting App Earns Its Cost

The ROI threshold for inventory forecasting tools is roughly: 50+ SKUs with at least 2 months of sales history, or any store where stockouts are a recurring problem. Each stockout costs you the gross profit on the lost sale plus potential long-term customer value. A single stockout on a $50 product with 50% margin costs $25 in gross profit. If a forecasting tool prevents 10 stockouts per month, the $25 break- even on a $249/mo tool requires stopping 10 stockouts with 50% margins.

When forecasting tools underperform: stores with under 30 SKUs and stable demand (no seasonality, no product launches), stores where the buyer already has intuitive knowledge of reorder timing, or stores with very long and unpredictable lead times that render forecasts unreliable.

Pricing Comparison

AppFree TierEntry PaidMid TierStrength
Inventory Planner14-day trial$99/mo (Standard)$249/mo (Advanced)Most accurate forecasting algorithms
CogsyNo$79/mo (Starter)$199/mo (Growth)Best DTC-focused UX + ops workflow
Stocky by ShopifyFree (included)FreeFreeZero cost; basic replenishment reports

Prices as of May 2026. Stocky is Shopify's free built-in inventory app, available on all plans. It covers basic reorder point reports but lacks demand forecasting. Inventory Planner and Cogsy are paid tools for stores that have outgrown Stocky.

Stocky (Free, by Shopify)

Stocky is Shopify's built-in inventory management app — free on all Shopify plans. It provides: current stock levels, reorder point alerts based on average daily sales, purchase order creation within Shopify, and basic demand forecasting using a rolling average of past sales. For stores with under 50 SKUs and relatively stable demand, Stocky handles the core replenishment workflow without any additional cost.

Stocky's limitations become apparent at scale: its forecasting doesn't account for seasonality, promotional periods, or product lifecycle stages (a new product has insufficient sales history; a discontinuing product is over-ordered). It also has no supplier lead time modelling or safety stock calculation. For stores where these gaps cause repeated stockouts, the upgrade cost is usually justified.

Inventory Planner

Inventory Planner (by Sage) is the most analytically sophisticated forecasting tool in the Shopify ecosystem. It uses multiple forecasting models (exponential smoothing, linear regression, seasonal decomposition) and selects the best-fit model per SKU based on historical accuracy. This per-SKU model selection is the key differentiator: a seasonal product gets seasonal forecasting; a steadily growing product gets trend forecasting; a stable product gets simple average forecasting.

The purchase order workflow is the most complete: Inventory Planner generates recommended POs with suggested quantities, lead time adjustments, and safety stock buffers, which the buyer reviews and approves. This semi-automated workflow reduces the cognitive load of ordering across 200+ SKUs from multiple suppliers.

At $99–249/mo, Inventory Planner is the right choice for stores with 100+ SKUs, multiple suppliers, seasonal demand patterns, or where inventory buying is a significant part of a team member's job.

Cogsy

Cogsy is designed specifically for DTC brands — its interface is built around the operations workflow of a growing DTC team rather than the data-analyst-heavy UX of Inventory Planner. It pulls in planned marketing campaigns and expected sales lifts directly into the forecast (if you have a promotion planned for next month, Cogsy adjusts the reorder recommendation to account for the expected spike). This marketing-aware forecasting is genuinely differentiating for brands that run frequent campaigns.

At $79–199/mo, Cogsy sits between Stocky (free) and Inventory Planner's Advanced tier in both price and feature depth. It's the right choice for DTC brands where marketing drives demand spikes and the ops team wants a purpose-built tool, not a data export workflow.

Which One Should You Use?

Under 50 SKUs, stable demand, no seasonality
Stocky (free)Rolling average reorders are sufficient; no paid tool needed
50–200 SKUs, DTC brand with campaign-driven demand
Cogsy Starter ($79/mo)Marketing-aware forecasting; DTC-optimised workflow
100+ SKUs, multiple suppliers, seasonal patterns
Inventory Planner Standard ($99/mo)Per-SKU model selection; best forecasting accuracy at scale
Complex catalogue, need sophisticated PO automation
Inventory Planner Advanced ($249/mo)Full purchase order workflow + advanced safety stock modelling
On a paid forecasting tool, still running stockouts
Review lead time inputs and safety stock settingsTool accuracy depends on correct lead time data — most errors are config, not model

Paying for Inventory Forecasting You Don't Need?

AppTrim scans your Shopify billing history and flags inventory apps billing at tiers disproportionate to your SKU count. Inventory Planner Advanced at under 75 SKUs is a common overspend pattern — Stocky or Standard covers the same use case. Free scan, no credit card.

Scan My Inventory App Spend →

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