Calculator
Developer retainer calculator
Turn an hourly floor into a retainer that protects margin, covers coordination overhead, and prices urgency without guesswork.
A good retainer is not just hourly rate times hours. It also prices access, response expectations, and the meetings and context switching that come with ongoing client work.
Loading tool
Preparing interactive inputs
The calculator is loading its shareable state and interactive controls.
Example: product support retainer for one client
A solo consultant wants a recurring monthly package that covers delivery, comms, and a next-business-day response expectation.
Parameters
Results
Suggested monthly retainer
$4,911/month
Protected included-hours cap
20 hours
Recommended overage rate
$196/hr
Translate your hourly floor into a practical monthly retainer.
Bake coordination and response expectations into the quote.
Set a clean included-hours cap and an overage rate that protects margin.
Common questions
Explore more
Explore more billing workflows and tools
Move from one-off calculations into the pages that explain the full GitHub-to-invoice workflow.
Calculator
Freelance Developer Rate Calculator
Stop guessing your rate. Calculate a sustainable freelance developer hourly, day, and monthly rate from income goals, taxes, expenses, and real billable capacity. Free, no signup.
Calculator
Underbilling and Revenue Leakage Calculator
How much revenue are you losing to forgotten PRs? Estimate the hidden cost of manual billing — forgotten work, invoice prep time, and admin overhead. Free calculator.
Comparison
diffbill vs Toggl Track
Choose diffbill if you want consultant invoices built from merged pull requests and outcome-focused descriptions. Choose Toggl when simplicity in timer tracking matters more than GitHub-native billing.
Comparison
diffbill vs Clockify
Choose diffbill when your goal is faster, clearer client invoices from GitHub activity. Choose Clockify when you need broad team time tracking across roles that work outside GitHub.
Use case
Developer invoicing software for consultants
diffbill fits consultants whose delivery lives in GitHub. It turns scattered PRs and retainer work into clear invoice descriptions that clients approve without back-and-forth.
Use case
GitHub billing workflow for small dev agencies
diffbill helps small dev agencies standardize billing across accounts, eliminate the admin time spent rewriting technical updates, and deliver invoices that prove the value of every sprint.