Tool calibration due-date tracker for machine shops

B2BweekendWeb

StackNext.jsSupabaseStripe

Search demandMediumA steady stream of people are searching.
CompetitionLowThere are few direct competitors.
Customer valueHighA single customer can be worth a lot.
How scoring works

The idea

An ISO 9001 or AS9100 audit finding for an out-of-calibration micrometer is not a paperwork slap; it can cost a job shop its aerospace or medical customer, which might be half its revenue. Yet most 5-50 person shops track calibration in an Excel sheet owned by whoever set it up in 2014, with certificates in a filing cabinet and due dates in nobody’s calendar.

GAGEtrak and similar incumbents are clunky, desktop-era, and priced like enterprise QMS modules. The wedge is ruthless simplicity: import the existing spreadsheet, attach certificates, get emailed before anything goes overdue, and print the exact report the auditor wants to see, with the certificate PDF one click away.

Who pays

The buyer is the shop owner or quality manager at a small machine shop holding ISO 9001 or AS9100, at 39 USD/month flat - invisible next to what an audit finding costs. Distribution: SEO on calibration tracking spreadsheet searches, machining forums and r/machinists, and referrals from the calibration labs shops already send their gauges to.

MVP scope

  • Instrument register with CSV import, serials, intervals, and vendors
  • Calibration event logging with results and certificate PDF upload
  • 30-day and 7-day email alerts plus a weekly digest of due and overdue items
  • Printable ISO-auditor-ready status report and per-instrument history
  • Skip for v1: in-house calibration procedure management, measurement uncertainty tracking, multi-site support, barcode labelling
// Build prompt — paste into Cursor / Claude Code / Lovable / Bolt
Build GaugeGuard, a web app that keeps a machine shop's measurement
instruments in calibration and audit-ready. Stack: Next.js (App Router),
Supabase for Postgres, auth, and certificate file storage, Stripe for
billing. Magic-link auth.

Core flow: the shop builds an instrument register - each record has an
asset ID, type (micrometer, caliper, gauge block, thread gauge, etc.),
serial number, location, calibration interval in months, calibration vendor
(or in-house), and status (active, out for calibration, retired). Bulk CSV
import so a shop can move its Excel register in five minutes. When a
calibration is completed, the user logs it with date, result
(pass/fail/adjusted), certificate number, and an uploaded PDF certificate;
the next due date recomputes automatically from the interval.

Alerts: email the owner and the assigned person 30 days and 7 days before
each due date, plus a Monday digest listing everything due in the next 60
days and anything overdue. Overdue instruments get a prominent red state,
and the register supports an out-of-service flag with the ISO-expected
language.

The audit artefact: one click prints a calibration status report - every
active instrument with serial, last calibration date, certificate number,
next due date, and vendor - formatted cleanly for an ISO 9001 or AS9100
auditor, plus per-instrument history pages.

Pages: register with filters and search, instrument detail with history and
certificates, calendar of due dates, reports, settings. Pricing: 39
USD/month flat, unlimited instruments, 30-day trial via Stripe Checkout.

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