# Shiplines — Seller shipping calculator > Seller shipping calculator (iPhone/iPad app by Robert Corbin.) - Source: https://appshunter.io/ios/app/shiplines/id6777256265 (this page in markdown: same URL + `.md`) - Developer: [Robert Corbin](https://appshunter.io/developer/1890247992) - Category: Business, Utilities - Price: $2.99 - Age rating: 4+ - Requires: iOS 17.0 · 3 MB - Languages: American English - Released: 2026-06-10 - Data updated: 2026-08-11 - User reviews in markdown: https://appshunter.io/ios/app/shiplines/id6777256265/reviews.md ## What is Shiplines? Shipline is a fast offline shipping rate comparer for solo sellers. Enter a parcel - weight, dimensions, from-ZIP, to-ZIP - and instantly see what USPS, UPS, and FedEx will charge for the same shipment. No accounts, no scraping, no login. Designed for Etsy, eBay, Mercari, Poshmark, and Depop sellers who pack their own packages and want a per-shipment answer in under five seconds, not a quote workflow. WHAT SHIPLINE COMPARES - USPS Priority Mail - USPS Ground Advantage - UPS Ground - FedEx Ground EACH RESULT SHOWS - The price for that carrier, ranked cheapest first - Dollars saved by the cheapest option vs the next-best option - Estimated delivery window (business days) - The zone the calculation used - Whether dimensional weight beat the actual weight HOW SHIPLINE WORKS - 3-digit ZIP prefix centroids and distance bands map the route to a USPS-style zone 1-9 - Per-carrier dim divisors (USPS 166, UPS 139, FedEx 139) apply when box volume wins - USPS Priority and Ground Advantage bill in ounces under a pound; UPS and FedEx Ground round up to the next whole pound - All four pricings happen on this device against a baked-in 2026 reference table - no network call WHAT'S INCLUDED - Calculator tab with parcel template loader - Saved parcels - reusable weight + dim + route templates - History - last 30 quotes kept locally - Settings - default origin ZIP, weight unit preference, dimension unit preference, haptics toggle, More apps by Robert Corbin link PRIVATE BY DESIGN Shipline has no account, no ads, no analytics, no tracking, no subscription, and no developer backend. Saved parcels and history live in local app storage. There is no network access of any kind. ESTIMATES ONLY Rates are baked-in approximations from public 2026 published retail tables. A Disclaimer banner appears on every comparison reminding you to verify pricing with the carrier before purchasing labels. Shipline is a one-time paid utility for sellers who want the same-axis carrier answer without paying for an account or pulling out a calculator. ## Version history (last 5 releases) ### 2.0.1 — 2026-06-26 This update sharpens the interface: the iPad layout now uses a centered, comfortable reading width instead of stretching edge to edge, plus small display fixes. iPhone is unchanged. ### 2.0 — 2026-06-21 Shiplines 2.0 — a pro upgrade for sellers, still 100% offline. • Service Verdict: one clear "best service" recommendation across USPS, UPS, and FedEx, with the reason and the runner-up. • Target-Margin Pricer: price for the margin or markup you choose (20/30/40/keystone) — not just break-even. • Box Optimizer: spot dim-weight overage and the exact volume to shed to bill on real weight. • Packing Advisor: every flat-rate box your parcel fits, snuggest-first, with headroom. • Zone Spread: the cheapest cost to all 9 zones, for setting one flat shipping charge. No account, no network — every rate is computed on your device. ### 1.3 — 2026-06-17 Profit Lens: the Results screen now shows whether you'll actually make money on a sale. From the cheapest computed rate plus your saved selling costs (item cost, marketplace fee, payment fee, packaging) it gives you the free-shipping price threshold, your break-even price, and a slider to see your margin at any sale price — all on-device, no network. Set your costs under Settings → Profit Lens → Selling costs (Etsy/eBay/Mercari presets included), or tap "Edit fees" right on the card. Plus five reliability fixes: surcharge estimates now match the actual shipping zone, Compare requires complete ### 1.2 — 2026-06-15 Version 1.1 adds four substantive new features: Cubic Pricing Advisor — Many small, dense packages qualify for USPS cubic pricing, which bills by box volume instead of weight and can save $2–12 per shipment. After every calculation, Shipline now checks whether your parcel is eligible (≤ 20 lb, no side over 18 in, volume ≤ 1 cu ft for Ground Advantage or ≤ 0.5 cu ft for Priority Mail) and shows the cubic rate and exact savings when it beats the weight-based rate. Retail GA cubic rates are from the USPS Notice 123 effective April 26, 2026 and require no online account. Flat Rate Advisor — After every calculation, Shipline now checks whether a USPS flat rate envelope or box is cheaper than the zone-based Priority Mail price for that parcel. If the item physically fits inside a flat rate container and the price beats the computed rate, the alternative is shown directly on the results screen with exact dimensions and the dollar savings. Based on the USPS retail price schedule effective April 26, 2026. Surcharge Risk Warning — UPS and FedEx charge hidden "Additional Handling" and "Large Package" surcharges on parcels that exceed size or weight thresholds — fees that can range from $30 to over $270 and are not included in the base rate table. Shipline now automatically detects when your parcel crosses any of the 2026 trigger thresholds (longest side, second side, length-plus-girth, cubic volume, weight) and displays a visible warning with the triggering reason and an approximate surcharge amount, so you know before you buy the label. Share Quote — A share button on the results screen lets you export the full rate comparison as a plain-text summary for pasting into a message, listing DM, or email. The summary includes all four carrier rates, the cheapest marker, delivery windows, flat rate alternatives, and any cubic pricing savings found. ### 1.1 — 2026-06-14 Version 1.1 adds three substantive new features: Flat Rate Advisor — After every calculation, Shipline now checks whether a USPS flat rate envelope or box is cheaper than the zone-based Priority Mail price for that parcel. If the item physically fits inside a flat rate container and the price beats the computed rate, the alternative is shown directly on the results screen with exact dimensions and the dollar savings. Based on the USPS retail price schedule effective April 26, 2026. Surcharge Risk Warning — UPS and FedEx charge hidden "Additional Handling" and "Large Package" surcharges on parcels that exceed size or weight thresholds — fees that can range from $30 to over $270 and are not included in the base rate table. Shipline now automatically detects when your parcel crosses any of the 2026 trigger thresholds (longest side, second side, length-plus-girth, cubic volume, weight) and displays a visible warning with the triggering reason and an approximate surcharge amount, so you know before you buy the label. Share Quote — A share button on the results screen lets you export the full rate comparison as a plain-text summary for pasting into a message, listing DM, or email. The summary includes all four carrier rates, the cheapest marker, delivery windows, and any flat rate alternatives found. ## More apps by Robert Corbin - [Daily Word Journey](https://appshunter.io/ios/app/daily-word-journey/id6761548266) - [Hush Secret Text](https://appshunter.io/ios/app/hush-secret-text/id6761658175) - [Renew Guard](https://appshunter.io/ios/app/renew-guard/id6761755447) - [Receipt to PDF](https://appshunter.io/ios/app/receipt-to-pdf/id6761782025) - [Route Your Pay](https://appshunter.io/ios/app/route-your-pay/id6761783719) - [Tip Arbiter](https://appshunter.io/ios/app/tip-arbiter/id6761786879) All apps by Robert Corbin: https://appshunter.io/developer/1890247992 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-11.*