How to Check ISI Mark and CML Number on Plywood Online in 2026
To check the ISI mark on plywood, find the CM/L licence number (CM/L followed by 10 digits) printed with the IS 303 or IS 710 mark, then verify it in the BIS Care app (Verify Licence Details) or the Status of Licence search on BIS Manak Online. Since February 2025, every plywood sheet sold in India must carry a valid ISI mark.
Last updated: . Grades and standards checked against current BIS standards.
CML number check for plywood: the quick answer
Every ISI-marked plywood sheet carries a BIS licence number written as CM/L followed by 10 digits, printed with the ISI logo and the standard the sheet is made to, such as IS 303 or IS 710. To check it:
- Find the ISI mark on the sheet's face or edge and note the full CM/L number and the IS number.
- Open the BIS Care app and choose Verify Licence Details, then enter the CM/L number.
- Or use the Status of Licence search on BIS Manak Online, enter the number after "CM/L-" and click Generate Report.
- Check that the result shows an operative licence for plywood under the same IS number, and that the licence holder matches the brand or its contract maker.
- If anything does not match, do not pay: ask the dealer to explain, and report suspected misuse to BIS.
Since February 2025, a BIS Quality Control Order makes the ISI mark mandatory for plywood sold in India, so this check applies to every sheet you buy, branded or local.
Why verifying the ISI mark matters
The ISI mark tells you the maker holds a BIS licence for that product and that its production is tested against an Indian Standard: bond strength, moisture content, formaldehyde class and, for each grade, a water test. Look-alike marks still turn up in wholesale markets, and a printed "710" or "ISI" on its own proves nothing. A two-minute check of the CM/L number is the only way to know the licence is real and current. See also how to identify fake plywood.
What the ISI mark on plywood shows
- ISI logo: the BIS standard mark.
- IS number: the standard the sheet is made to: IS 303 (general purpose, MR, BWR and BWP grades), IS 710 (marine), IS 5509 (fire retardant) or IS 10701 (structural).
- CM/L number: the BIS licence number, "CM/L-" followed by 10 digits. This is your verification key.
- Grade and class: for IS 303, the grade (MR, BWR or BWP) and the formaldehyde class (E1 or E2).
- Maker and batch details: the manufacturer or brand, and usually thickness and batch or date codes.
Read more in how to read plywood labels and what the ISI mark means.
IS 303 vs IS 710 markings
IS 303:2024 is the general-purpose standard and has three grades: MR for dry interiors, BWR for humid areas and BWP for wet areas. BWP was added in the 2024 revision. IS 710:2024 is the marine standard: it also uses a 72-hour boil test, and adds minimum glue strength and preservative treatment. So a boiling water proof sheet can be marked IS 303 BWP or IS 710. A genuine mark states the exact standard; a sheet that only says "ISI certified" or "710" without a CM/L number is a red flag.
Where to find the mark on a sheet
- Look on the face near one corner and along the long edges; some makers print the mark on the back face.
- In a stacked bundle, ask the dealer to pull out a sheet so you can read the full mark.
- Photograph the mark, including the full CM/L number, before the sheets are loaded.
- Red flags: a sticker instead of a print, a smudged or partial number, or no CM/L number at all.
Method 1: check the CM/L number in the BIS Care app
The BIS Care app, published by the Bureau of Indian Standards for Android and iOS, is the fastest way to check at the dealer's counter.
- Install BIS Care from Google Play or the App Store.
- Open Verify Licence Details.
- Enter the CM/L number exactly as printed and submit.
- Read the result: licence holder, address, product, IS number and licence status.
The app also has a complaints section for reporting suspected misuse of the ISI mark. Brand QR codes on some sheets are warranty or authenticity systems run by the brand; they are useful, but they are not a BIS licence check.
Method 2: check the licence on BIS Manak Online
BIS's Manak Online licence reports page lets you search licences on a computer:
- Open the page and go to Status of Licence.
- Enter the digits after "CM/L-" in the Licence No field and click Generate Report.
- To see every licence for a standard, use List of Licences: choose the IS number (for example IS 303 or IS 710), a state and the status, then Generate Report.
- To rule out a lapsed licence, check Licences Cancelled/Expired for the same IS number.
| What the result should show | What it means if it does not |
|---|---|
| Status: operative | A cancelled, expired or "under stop marking" licence should not be used on new sheets |
| Product: plywood, with the same IS number as the sheet | A licence for a different product or standard does not cover this sheet |
| Licence holder matching the brand or its contract maker | A different firm can mean a copied number; ask the dealer for the brand's own confirmation |
| A complete CM/L number (10 digits) | A short or partial number cannot be verified |
Genuine vs fake ISI marks
| Feature | Genuine mark | Warning sign |
|---|---|---|
| ISI logo | Clean, correctly proportioned print | Blurred, distorted or stuck-on logo |
| IS number | Exact standard, such as IS 303 or IS 710 | Only "ISI plywood" or a bare "710" |
| CM/L number | "CM/L-" plus 10 digits that verify online | Missing, shortened or not found in BIS records |
| Grade | MR, BWR or BWP stated for IS 303 sheets | Grade missing or contradicting the invoice |
| Paperwork | GST invoice naming brand series, grade and thickness | Cash sale or vague "waterproof" description |
Plywood standards quick reference
| Standard | Covers | Key requirement |
|---|---|---|
| IS 303:2024 | General-purpose plywood: MR, BWR and BWP grades | MR: 3-hour soak at 60°C, three cycles. BWR: 8-hour boil, three cycles. BWP: 72-hour boil. Moisture content 5-15%; formaldehyde class E1 or E2 |
| IS 710:2024 | Marine plywood | 72-hour boil, minimum wet and dry glue shear strength, pressure preservative treatment (ACC or CCB at 12 kg/m³ minimum) |
| IS 5509:2021 | Fire-retardant plywood | Flammability and flame-spread tests |
| IS 10701 | Structural plywood | Strength requirements for load-bearing use |
"E0" is a brand label, not a BIS class; ask for the test report if a sheet is sold on an E0 claim. More on grades: MR vs BWR vs BWP and ISI standards in the plywood industry.
Physical checks that back up the licence check
- Edges: even veneer layers with no gaps or overlaps in the core.
- Thickness: measure at several points; it should match the stated size closely.
- Knock test: a hollow sound in one area suggests a void in the core.
- Weight: compare sheets of the same thickness; an unusually light sheet often has a weak core.
More tests: how to check plywood quality.
If the check fails: what to do next
- Do not pay or accept delivery until the dealer explains the mismatch in writing.
- Ask for the brand's confirmation of the batch, or choose another sheet whose licence verifies.
- Report suspected misuse through the BIS Care app's complaints section, with photos of the mark and the dealer's details.
- Keep the GST invoice; it should name the brand series, grade, thickness and quantity.
Advice by buyer type
- Homeowners: verify before you pay, and register brand warranties where the brand offers it. See plywood warranties explained.
- Contractors: check the CM/L number on every lot, not just the first delivery.
- Architects and designers: write the standard, grade and formaldehyde class into the BOQ, and ask for licence details with the quote.
Frequently asked questions
Is the ISI mark mandatory for plywood?
Yes. Since February 2025, a BIS Quality Control Order requires plywood sold in India to carry the ISI mark under a valid licence. Unmarked sheets cannot legally be sold.
How many digits does a CM/L number have?
Ten digits after "CM/L-". A shorter number cannot be verified and should be treated as suspect.
Can I check a CML number online without the app?
Yes. Use the Status of Licence search on BIS Manak Online and enter the number after "CM/L-".
The licence shows as expired or under stop marking. What now?
Do not buy the sheet on that licence. Ask the dealer for stock under an operative licence, or choose another brand.
Does an ISI mark mean the plywood is waterproof?
No. It means the sheet meets its grade. MR is for dry areas, BWR for humid areas, and only BWP or marine (IS 710) is built for wet areas. Check the grade printed with the mark.
A dealer says the plywood is "lab tested". Is that enough?
No. A private test report does not replace the BIS licence. Ask for the CM/L number and verify it.
Sources: BIS Manak Online licence reports, the BIS Care app (Verify Licence Details), BIS standards IS 303:2024 and IS 710:2024, and trade reports on the 2025 Quality Control Order for wood-based panels. Checked on 15 October 2026. PlyPrice is an independent buyer's guide.
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