Built for small businesses that grow

Run your business
from one place.

Project management, invoicing, time tracking, and an AI advisor that knows your numbers — in one product. Stop stitching together five tools that don't talk to each other.

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Why Mainspring

Three things every other PM tool can't do

Differentiator
Acme Co.
Hi, Client
Website Redesign
67%
$3.2K
outstanding
✓ Wireframes completed2d
✓ INV-001 paid5d
○ Design reviewdue Mar 5

Your clients don't need an account

Generate a branded read-only link for any project. Clients see status, progress, outstanding invoices, and recent activity — without ever signing up for Mainspring.

  • Read-only project view, branded with your colors
  • No client signup required — just send the link
  • Revoke or expire links any time
AI Native
Where's my biggest growth opportunity this quarter?
Your Q2 Launch project is at 42% margin — your highest. You have $3.2K in unbilled hours on it. Send the next invoice this week to free up cash flow.
Pricing strategyCash flow

An AI advisor with your numbers

Ask “Where's my biggest growth opportunity this quarter?” and get an answer grounded in your actual revenue, projects, and time tracked — not generic advice.

  • Live business context auto-piped to GPT-4
  • Insight cards: revenue, outstanding, top projects
  • Aggregates only — no row-level data leaves your org
One Product
Revenue
$24K
Hours
187
Projects
5
To Do
Design hero
Write copy
Doing
Build CMS
Done
Wireframes
INV-002 sent · $3,276

PM, invoicing, and AI together

Stop paying for Asana plus Harvest plus FreshBooks plus ChatGPT. Mainspring is one tool — and the data flows between them so you don't lose context.

  • Tracked time auto-feeds into invoice line items
  • Project budgets reconcile against actual expenses
  • AI sees everything, advises on everything

See it in action

Watch the 90-second tour

See exactly how Mainspring fits together — from kicking off a new project to invoicing the client and getting AI-flagged risks before they become problems.

Prefer to click around yourself? Try the interactive demo →

What else is included

All the workflow basics — plus the parts other tools charge extra for

Kanban + Gantt

Drag tasks between columns or zoom out to a project timeline.

Time tracking

Log hours per task; roll-up to projects, clients, and invoices.

Multi-task templates

Reusable checklists with day-offset due dates. Spawn an entire onboarding in one click.

Live reports

Revenue, time, expenses, project health — exportable to CSV.

Role-based access

Admin / member / viewer roles with row-level security on every table.

White-label brand

Your colors, your logo — clients never see "Mainspring" unless you want them to.

Ready to consolidate your stack?

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