What is the difference between acceptable and permissible limits in IS 10500?

The acceptable limit is the value IS 10500 recommends you meet. Values above it render the water not suitable, but may be tolerated in the absence of an alternate source, up to the permissible limit. Above the permissible limit, the standard says the source has to be rejected.

What does “no relaxation” mean in IS 10500?

It means there is no permissible limit above the acceptable one, so the acceptable limit is the only limit. It applies to pH (6.5 to 8.5), nitrate (45 mg/L), iron (1.0 mg/L), arsenic (0.01 mg/L), lead (0.01 mg/L), every toxic substance and every pesticide, among others.

Is a result equal to the limit within IS 10500?

Yes. IS 10500 writes its limits as maximums (Max), so a TDS of exactly 500 mg/L is within the acceptable limit and a pH of exactly 8.5 is within 6.5 to 8.5. Your lab's decision rule may still set a stricter acceptance limit if it takes measurement uncertainty into account.

What is the TDS limit for drinking water as per IS 10500?

The acceptable limit is 500 mg/L and the permissible limit, in the absence of an alternate source, is 2000 mg/L. A TDS of 400 mg/L is within the acceptable limit, 1500 mg/L is within the permissible limit only, and 2500 mg/L exceeds the limit.

Can I use this checker for RO water or packaged drinking water?

For water from an RO purifier at home or in an office, yes: IS 10500 covers water intended for drinking and cooking from any source. Packaged drinking water and mineral water are judged against FSSAI regulations and their own BIS product standards, IS 14543 and IS 13428, not IS 10500.

Is the checker's result the same as a test report?

No. It is a screening aid that compares numbers you type with the IS 10500 limits. A test report comes from the laboratory, using its own validated methods. Under ISO/IEC 17025, which NABL accredits labs against, a report that states conformity must also state the decision rule used.

IS 10500 water test report checker (free)

Check results against IS 10500

Choose the parameters on your report, then type each result in the unit shown. For a result below your reporting limit, type it with a < sign, like <0.001.

Choose parameters (16 parameters selected)

Sample name or report number (optional, for the summary)

Limits are from IS 10500:2012 with Amendments 1 to 4. The checker runs in your browser and sends nothing anywhere. It compares each result exactly as you type it, so round it the way your method requires first.

What the results mean

Within acceptable limit: the result meets the limit IS 10500 recommends.
Within permissible limit †: the result is above the acceptable limit but within the higher permissible limit. The standard tolerates this only where no alternate source exists. Only parameters that have a separate permissible limit can land here.
Outside the limit *: the result is above the permissible limit, or above the only limit where there is no relaxation, or outside the pH range, or bacteria were detected, or odour or taste is not agreeable.
Cannot judge: you typed a reporting limit, like <0.05, that is higher than the IS 10500 limit, so the result could be on either side of it.

Below the results, the checker counts how many fall in each group and builds a summary table with the same † and * marks, which you can copy into Excel or a worksheet, or print.

Acceptable and permissible limits: the difference

For many parameters IS 10500 gives two limits. The note under Tables 1 to 4 explains how they work: “It is recommended that the acceptable limit is to be implemented. Values in excess of those mentioned under ‘acceptable’ render the water not suitable, but still may be tolerated in the absence of an alternative source but up to the limits indicated under ‘permissible limit in the absence of alternate source’ in col 4, above which the sources will have to be rejected.”

So a result within the permissible limit is not a plain “complies”. It exceeds the acceptable limit, and the water is tolerated only if there is no other source. A report should say so.

Where the permissible column says “No relaxation”, the acceptable limit is the only limit. That covers pH, ammonia, barium, chloramines, iron, mineral oil, nitrate, selenium, silver, sulphide, every toxic substance in Table 3, both radioactive parameters and every pesticide. For the full list with test methods, see our guide to IS 10500 drinking water standards.

How the checker judges each result

Type of limit	Example	How it is judged
Maximum with a permissible limit	TDS: 500 / 2000 mg/L	Up to 500 is within acceptable, above 500 up to 2000 is within permissible, above 2000 is outside the limit.
Maximum with no relaxation	Nitrate: 45 mg/L	Up to 45 is within acceptable; anything above is outside the limit.
Range	pH: 6.5 to 8.5	From 6.5 to 8.5 is within acceptable; anything else is outside the limit. There is no relaxation.
Minimum	Free residual chlorine: 0.2 mg/L	At least 0.2 is within acceptable; below 0.2 is outside the limit. It applies only when the water is chlorinated.
Agreeable	Odour, taste	Choose agreeable or not agreeable.
Not detectable	E. coli, coliforms in 100 mL	Not detected meets the requirement; detected is outside the limit.

A result equal to the limit counts as within it, because IS 10500 writes its limits as maximums. A result typed as <0.001 counts as within the acceptable limit when 0.001 is at or below that limit. The checker also applies the remarks in the standard that change a verdict or need a note:

Sulphate may go up to 400 mg/L only if magnesium does not exceed 30 mg/L. Enter magnesium and the checker applies this.
Colour may be extended to 15 Hazen units only if toxic substances are not suspected.
Iron and manganese: the remark that their total shall not exceed 0.3 mg/L was left unchanged when Amendment 1 raised iron to 1.0 mg/L. The checker flags a total above 0.3 and leaves the decision to your lab.
Total coliforms apply to treated water entering or in the distribution system, not to an untreated bore well, open well or hand pump.
Free residual chlorine: IS 10500 prints 1 in the permissible column without calling it a maximum. The checker notes a result above 1 mg/L and leaves the decision to your lab.

Worked example: a bore well report

Press Fill an example in the checker to load 14 results. Four of them, and the summary:

TDS 920 mg/L	Above 500, within 2000: within permissible †
Fluoride 1.3 mg/L	Above 1.0, within 1.5: within permissible †
Nitrate 52 mg/L	Above 45, no relaxation: outside the limit *
Total arsenic <0.005 mg/L	Reporting limit below 0.01: within acceptable
Summary for all 14 results	9 within acceptable, 4 within permissible only, 1 outside the limit

This well does not meet IS 10500 because of nitrate. Even without the nitrate result, its TDS, total alkalinity, total hardness and fluoride would make it a source to use only if no alternate source exists.

What this checker does not do

It is not a legal pass or fail for every use. IS 10500 is the specification for drinking water. Packaged drinking water and mineral water are judged against FSSAI regulations and their BIS product standards (IS 14543 and IS 13428). Treated effluent, and water for construction or industry, are judged against their own standards, consents or customer specifications. Whether IS 10500 binds a particular supply depends on who adopts it: Jal Jeevan Mission, for example, uses it as the quality norm for piped water.
It is not a test report. The lab's report must follow the lab's own validated method and NABL's requirements. Under ISO/IEC 17025 clause 7.8.6, a report that states conformity must say which results and which specification it covers, and the decision rule applied. A decision rule that allows for measurement uncertainty can give a different answer near a limit. This checker uses simple acceptance: the result is compared straight with the limit.
It does not convert units. Type each result in the unit shown. Nitrate is as NO₃, so a result reported as nitrate-nitrogen must be multiplied by 4.43 first. Ammonia is as total ammonia-N. Pesticides are in micrograms per litre (µg/L), not mg/L.
It does not cover MS2 phage, Cryptosporidium or Giardia. These virological and biological requirements sit in clauses 4.2 and 4.3, not in the tables.

Where Tanush LIMS fits

If your lab checks IS 10500 limits by hand on every report, Tanush LIMS does it as each result is calculated. IS 10500:2012 (Amd 1–4) comes built in with both limit columns. Your Technical Manager reviews and activates it once, and from then on it is pre-selected for drinking water, bore well, tap, hand pump and open well samples. The review screen shows Complies, Within permissible † or Does not comply beside each result. The report prints Acceptable limit and Permissible limit columns, marks a result within the permissible limit with † and one outside the limit with a red *, each with its footnote. It runs on your lab's own PC, even without internet, or in the cloud. NABL accredits laboratories, not software. See Tanush LIMS for water testing labs or book a demo.

Sources

Bureau of Indian Standards, IS 10500:2012 Drinking Water: Specification (Second Revision), copy with Amendment No. 2, National Consumer Helpline, Government of India
Bureau of Indian Standards, IS 10500:2012 text, Public.Resource.Org copy
Bureau of Indian Standards, Amendments No. 1 (June 2015), No. 3 (February 2021) and No. 4 (November 2021) to IS 10500:2012, in a BIS-issued copy reproduced here (pages 17 to 22)
Ministry of Jal Shakti, Drinking Water Quality Monitoring and Surveillance Framework (2021), the source of the 16-parameter common set
NABL, NABL 220 document review checklist, with the text of ISO/IEC 17025:2017 clause 7.8.6

IS 10500 water test report checker

Check results against IS 10500

Summary table

IS 10500:2012 (Amendments 1 to 4) result check