Drop your JEE Main photo, get a JPG inside the NTA window — photo 10–200 KB, signature 10–100 KB (set Target to 100 KB and Min to 10 KB for it). Nothing is uploaded; it runs in your browser.
The NTA application form for JEE Main takes two scanned images, each JPG/JPEG with an enforced size window: the photograph at 10–200 KB and the signature at 10–100 KB. Both ends of each window are enforced — a signature under 10 KB is rejected just like an oversized one. This page is preset to the photo window (10–200 KB). For the signature, change Target to 100 KB and Min to 10 KB above; a tight signature crop at high quality can land under the 10 KB floor, in which case PixFit pads the file up with a spec-valid JPEG comment (plain-text padding bytes; no pixels change, portals accept it). The form expects the files to be named Photograph and Signature — rename the downloads before uploading.
Both windows changed. Older guides — and old NTA error messages still quoted in forum threads — say the photo may be up to 300 KB and the signature must be 4–30 KB. For the 2026 cycle NTA reduced the photo ceiling to 200 KB and raised the signature window to 10–100 KB, and current sources agree on those figures (one big coaching site still says 10–50 for the signature — that's the stale-copy problem this paragraph exists for). If the Information Bulletin for your session prints different numbers, the bulletin wins.
NTA states the photograph as a passport-style print — about 3.5×4.5 cm — and the signature strip as roughly 3.5×1.5 cm, but publishes no pixel counts. Keep the photo in passport shape (a 200×230 or 276×354 crop both work — type either into Exact size above if you want it exact) and the signature a wide strip cropped close to the ink. If the upload screen itself states pixel dimensions, those win.
The photograph must be a recent colour passport-style photo on a white background with about 80% of the face visible including both ears — no cap or mask (regular spectacles are fine), and Polaroid or computer-generated photos are rejected. The signature goes on white paper in black or blue ink, in running hand — all-capitals signatures are treated as invalid, and the signature you produce on exam day is compared against it. PixFit fixes bytes and pixels only; the Information Bulletin on jeemain.nta.nic.in is the authority if it disagrees with anything here. Also sitting NEET (UG) or CUET? Their windows differ: see the NEET page and the CUET UG page.
These files identify you — face and signature, tied to your application number. PixFit re-encodes them entirely in your browser: nothing is uploaded to any server, and the re-encode strips EXIF metadata (including GPS) from phone photos as a side effect. An iPhone HEIC can be dropped straight in; the JPG it produces is what you upload.