Every calculator follows the rule written in its official source, and that source is linked at the bottom of the page with the date it was last checked. This page explains how that is done, and — just as important — what is left out when it cannot be done honestly.
Where the figures come from
Each page starts from a document, not from another website: the exam notification, the pay order, the government resolution or the university regulation. The figures in it are written into a data file that records the source URL and the date it was verified, and the page is generated from that file. Nothing is typed in twice, so a page cannot contradict the source it cites, or another page that uses the same rule.
When a figure is worked out rather than quoted
Some things are not printed in the notification and have to be calculated. Where that happens the page says so in plain words instead of presenting the result as a quotation.
The commonest case is a range of dates of birth. Many notices print an age limit and a crucial date but no dates of birth at all — the Uttarakhand Police advertisements are one example. The range shown is then worked out using the reckoning government advertisements use when they do print it: you must not have attained the maximum age on the crucial date, so for an upper limit of 28 years on 1 July 2024 the earliest allowed date of birth is 2 July 1996, not 1 July 1996. The page states that the dates are derived and explains the reckoning, so you can check it yourself.
When two official sources disagree
It happens more than you would expect. A district website and the Census handbook give different areas and populations for the same district. Where two official sources conflict, both figures are shown with their sources, rather than one being chosen silently. Facts that official sources disagree about are also kept out of the practice questions, so that no question ends up with two defensible answers.
What is deliberately left out
If a figure cannot be found in an official document, it is not published. Several calculators that would be useful, and that other sites do publish, are missing for exactly this reason: the rules could not be reached on any government host, or the notice does not state the number. The gap is recorded and revisited when a document appears, rather than filled in from a coaching site or from memory.
The same applies to predictions. Where an authority publishes no mapping — a percentile-to-rank table, for instance — none is invented. Tools show the range the official data supports and stop there.
Rounding
- Rounding happens only where the official rule says to, and in the way it says.
- Grade point averages (SGPA and CGPA) are rounded to 2 decimal places, as the UGC guidelines require, unless a university's own rule says otherwise.
- Pay amounts are shown in whole rupees, with 50 paise and above rounded up, which is how government pay orders round.
- Exam marks are added up exactly — a penalty of 1/3 or 5/18 of a mark stays an exact fraction — and rounded once at the end.
Negative marking
A penalty is applied as the notice defines it, which is not always a fixed number of marks. Several notices deduct a fraction of the marks assigned to that question, so the deduction depends on what each question is worth. In the CDS written exam, for example, English and General Knowledge put 100 marks over 120 questions, which makes a question worth five sixths of a mark and a wrong answer cost 5/18 — while Elementary Mathematics, at 100 marks over 100 questions, costs exactly one third. Applying a flat one third everywhere would overstate the penalty in two papers out of three.
An unattempted question never carries a penalty, and a page says so wherever a notice confirms it.
Dates and age limits
Age is counted on the crucial date the notice prints, not on the date you apply. Where the notice prints the range of allowed dates of birth, that range is used exactly as written; where it does not, the range is derived and labelled as described above. A category relaxation moves only the earliest allowed date of birth, by the number of years the notice allows, and relaxations are applied one at a time unless the notice says they can be combined.
Pay
Salary calculators use the official pay matrix, the Dearness Allowance rate in force on the date you choose, and the House Rent and Transport Allowance rules from the relevant orders. State employees are calculated from their own state's matrix, allowances and orders, never from the central ones. Income tax is not included unless a page says so.
Personal data in official documents
Some official result documents list candidates by name, roll number and date of birth. Those details are never reproduced here, even though the source is public. Only aggregate figures, such as category cut-off marks, are used, and an automated test enforces it.
Both languages, one set of facts
Hindi and English pages are generated from the same data and the same shared configuration, so a figure cannot be right in one language and wrong in the other. The downloadable reference files are generated from that same data too, which is why no older version of a file is kept: the current one is the only one that matches the site.
Testing and checks
Every engine is tested before it is written, and the tests include the worked examples printed in the official documents, cases exactly on each boundary, every relaxation category, and invalid input. Beyond that, the build itself refuses to publish: data files are validated against their schemas, every internal link and source link must resolve, every page must carry its sources and check date, and a page that has drifted from the data fails the build rather than going live quietly. A change that breaks any of this cannot be published.
Keeping it current
A job runs every morning against 21 government notice boards — the exam bodies, commissions and departments whose rules this site uses — and records anything new it finds. It never changes a figure by itself; it only flags what to read. When a notice appears, the document is downloaded and verified before any number moves, and the "last checked" date on the page is what that verification produced.
Your data
All calculations run in your browser. The marks, dates of birth and pay figures you type are not sent to this site and are not stored. The privacy policy sets out everything the site loads, including the analytics that measures which pages are read.