Professional
Save and monitor deadlines
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View ProfessionalCalculate a procedural deadline.
See the cited rule and working. Save it to a matter when it needs monitoring.
Start with the matter location and deadline.
Choose an exact deadline result to open it preselected, or choose a court or tribunal.
Work backwards from a deadline
Pick a target date and find the latest trigger date that still meets it.
Reviewed June 2026 · CPRReview coverage and exclusions
Advanced options · Browse by area of law
A result you can inspect
The date never arrives as a bare answer.
Every completed calculation keeps the triggering event, the selected rule, its citation and the ordered calculation steps together. That makes the result quicker to review against the current source before it enters your diary.
- The jurisdiction and forum selected
- The triggering event and date
- The rule ID, version and citation
- Every counting and calendar adjustment
- The final date and any warnings
Acknowledgment of service, England & Wales
Claim form and particulars posted by first-class post, Wednesday 10 June 2026
Deemed serviceFriday 12 June 2026
The second business day after posting
CPR 6.14Period appliedFriday 26 June 2026
14 days to file the acknowledgment, counted from deemed service
CPR 10.3(1)Calendar checkFriday 26 June 2026
26 June 2026 is a business day, so no roll-over is needed
CPR 2.8Acknowledgment of service dueFriday 26 June 2026
Illustrative result. Check the selected rule, current source and matter facts.
What Professional adds
Follow a calculation after it is saved.
Step through the workflow. See the result enter a matter, reach a subscribed calendar and change without erasing the calculation that came before it.
See ProfessionalIllustrative product demonstration.
Calculation ready. The defence deadline is 7 July 2026.
Matter timeline
Harwood v Lyle Logistics
Defence due
07/07/2026
Claim form served · 14-day period
Calculation complete
10:42Defence due 07/07/2026
CPR 15.4 · ready to save
This demonstration changes only the example above. It does not save your data.
Common deadline checks
Start with the deadline you need.
Open a focused calculator with the relevant rule selected. The full catalogue covers 4,871 rules across 20 jurisdictions.
Civil Procedure Rules
Deemed service
Work out the deemed date of service for a claim form or any other document under CPR 6.14 and 6.26: post, DX, email, fax and personal service, with business days applied.
second business dayCPR 6.14Open calculator
Civil Procedure Rules
Acknowledgment of service
Calculate the 14-day time limit to file an acknowledgment of service under CPR 10.3, and what follows it: the 28-day defence window and default judgment exposure.
14 daysCPR 10.3Open calculator
Civil Procedure Rules
Defence
Calculate the time limit to file a defence: 14 days from service of the particulars, or 28 days where an acknowledgment of service was filed (CPR 15.4), with counterclaim and default judgment windows.
14 daysCPR 15.4(a)Open calculator
Civil Procedure Rules
Part 36
Calculate Part 36 deadlines: the 21-day relevant period, 14 days to pay an accepted offer, and the 7-day clarification window, each cited to its rule.
21 daysCPR 36.5(1)(c)Open calculator
Civil Procedure Rules
Civil appeals
Calculate the time limit to file an appellant's notice: 21 days under CPR 52.12(2)(b), the 7-day oral reconsideration window and the 28-day statutory appeal period.
21 daysCPR 52.12(2)(b)Open calculator
Employment Tribunal
ET time limits
Calculate employment tribunal time limits: three months less one day for unfair dismissal and discrimination, six months for redundancy pay and equal pay, with ACAS Early Conciliation extensions applied.
3 months less 1 days.111 ERA 1996Open calculator
Simple pricing
Choose how you want to keep the calculation.
Professional monitors a matter. A one-off PDF puts one eligible calculation on file. Checkout shows the price in your currency.
England & Wales prices shown in GBP
One-off PDF record
Put one eligible calculation on file
£4.99
one-off · no subscription
A permanent PDF with the inputs, working and citations.
Calculate for a PDF recordFree
Calculate and check a deadline
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Calculate free, with the citation and steps shown.
Calculate freeMethodology
Rule-based calculation.
The trigger, period, direction, counting method, calendar and citation are applied in a repeatable calculation you can inspect.
How the engine countsWhat is included
See what each calculator covers.
Each jurisdiction page publishes its included forums, source collections and known exclusions. Court orders, local practice and fact-specific discretion are not silently inferred.
Inspect jurisdiction coverageReview status
Dates and changes are visible.
Coverage pages show their compact rule-review date. Published rule changes are retained in the change log and connected to affected saved matters when possible.
Read the rule change logBefore you calculate or buy
Deadline Engine calculates the procedural deadlines listed on each jurisdiction page. The current catalogue contains 4,871 deadline rules across 20 jurisdictions. Each page shows what is included, when its rules were reviewed and what still needs checking.
Deadline Engine applies the selected rule and shows the citation and calculation steps. It is calculation software, not legal advice, so check the current source, any order and the facts of your matter.
Free gives you the date, citation and calculation steps. Professional saves and monitors deadlines across your matters, with calendar feeds, recalculation history, rule-change warnings and exports.
The formal Evidence Record is a one-off PDF containing the jurisdiction, forum, triggering event, inputs, result, rule ID and version, citation, calculation steps and generation time. It does not start a subscription.
Professional recalculation creates a new version and retains the earlier record. A changed published rule can identify saved matters that may be affected, without silently overwriting their history.
No account is needed to calculate deadlines. An account is required to save and monitor matters with Professional.
Start with the date. Pay only when you want it monitored.
Calculate free with the citation and working visible. Then save the result to a matter or buy a PDF calculation record when the file needs more than an answer.
Deadline Engine is a Thesmios Ltd product. It provides procedural calculation software, not legal advice. Verify the current rule and matter facts.