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DSO Calculator

Days Sales Outstanding measures how long it takes you to get paid on average. Paste your invoices (paid or open) and we'll calculate it plus benchmark against UK SMB averages.

Your DSO (weighted average)Average

38 days

Based on 3 invoices (£4,850 total revenue). 1 still open — counted to today.

UK SMB benchmarks: under 25 days excellent · 25-35 healthy · 35-50 average · 50-70 slow · 70+ critical.

Want this on every invoice?

Zentra Collect runs this engine on every overdue invoice.

Statutory interest auto-applied, customer payment portal embedded in every chase, AI-drafted messages with tone control. Start free.

Estimate only — not legal or accounting advice. Verify with a qualified professional.