Resize Image to 50x20 mm
Upload your photo and instantly resize it to exactly 50x20 mm. Perfect for exam forms, passports, and precise digital requirements.
Some application forms ask for a signature that fits a 50×20 mm (5×2 cm) box. This client-side tool scales and center-crops your signature image to that shape, which works out to 590×236 pixels at 300 DPI, and exports a JPEG file. The image is processed inside your browser, so your signature is not uploaded anywhere.
The tool center-crops your image to a 2.5:1 aspect ratio and executes a compression loop targeting a file size between 30 and 49 KB to comply with Railway Recruitment Board standards. Because center-cropping cuts off any image portions extending past the 2.5:1 boundary and the tool cannot clean up paper shadows, you should upload an image taken in good light on unlined white paper with balanced margins.
How it works
1. Step 1 — Upload Photo
Click “Upload Photo” or drop your signature file into the area. Any current browser can open a JPG, PNG or WEBP signature scan. A HEIC photo from an iPhone camera loads in Safari only; elsewhere, save it as JPG first.
2. Review Specifications
Examine the preset specifications panel showing 590×236 Pixels, 50×20 mm in Millimeters, 300 DPI Resolution, and the 30–49 KB File Size target range.
3. Resize Photo
Click “Resize Photo”. While processing, the button displays “Processing...” as it draws the image to canvas and runs a binary search across JPEG quality settings.
4. Step 2 — Download Result
Review the status. If the file falls between 30 KB and 49 KB, it displays “Ready to use”. If the compressed file is below 30 KB, the tool pads it to 30 KB so portals with strict minimums accept it. If it exceeds 49 KB even at quality 0.1, it saves at quality 0.9 with the status “File size outside target range”. Click “Download” to save the signature.
When you'd use it
Railway recruitment notices that use a 50×20 mm box
RRB’s CEN 06/2024 for Non-Technical Popular Categories (Undergraduate) gave the signature as 50 mm x 20 mm or 140 x 60 pixels. Later notices can change this, so check the CEN you are applying under.
Any form that asks for a 5×2 cm signature
If your instructions ask for a 5 cm by 2 cm signature, this preset produces that 2.5:1 shape directly instead of you cropping by eye.
College and scholarship forms with a signature upload
Preparing a neat, compressed signature file for an online admission or scholarship form, after checking that form’s own size and KB rules.
Keeping a ready-made wide signature file
Saving a cleanly cropped 2.5:1 signature on your device so you have a starting point the next time a form asks for one.
What recruitment notices say: RRB and UPSC
Railway Recruitment Board CEN 06/2024 (NTPC Undergraduate), published on rrbsecunderabad.gov.in, asks applicants to sign on white paper with a black ink pen, in running letters and not in block letters, as a JPEG with “Dimensions of 50 mm x 20 mm or 140 x 60 pixels (preferred)” and a file size between 30 KB and 70 KB. RRB’s later CEN 03/2025 (Paramedical Categories) changed the details: a scan box of 35 mm × 20 mm, at least 140 × 60 pixels and 100 DPI, 30–49 KB, and rejection for block, capital or disjointed letters or non-black ink. So 50×20 mm is not a fixed RRB rule; follow your own notice.
UPSC’s One Time Registration FAQ (https://upsconline.gov.in/upsc/OTRP/candidate/faq.php, accessed 2026-09-17) takes a different approach: the photograph and signature must each be between 20 KB and 300 KB, with a resolution from 350 × 350 pixels minimum to 1000 × 1000 pixels maximum (recommended 400 × 400 pixels), and the signature should be on white paper, preferably in black ink. That is not a 50×20 mm shape, so UPSC candidates should use a square preset rather than this 2.5:1 preset.
Resolution calculation: 50x20 mm to 590x236 pixels at 300 DPI
In physical measurements, 50 mm equals 1.9685 inches and 20 mm equals 0.7874 inches. At the standard 300 dots per inch (DPI) print density, multiplying by 300 gives 590.55 pixels wide by 236.22 pixels high. Rounded to whole pixels, this creates an exact 590×236 pixel canvas matching a 2.5:1 aspect ratio.
Because the tool performs a center crop, it cuts off anything outside this 2.5:1 rectangle. If your signature is long or placed high on the paper, the automated crop will slice off the top of tall letters or the end of your name. Sign in the center of the paper, leave generous white space around your signature, and crop your original photo neatly around the writing before uploading.
Understanding the 30–49 KB preset, padding, and file size status
TryDocsy’s 50×20 mm preset sets a target window of 30 KB to 49 KB, aligned with Railway Recruitment Board rules like CEN 03/2025 where files below 30 KB or above 49 KB are rejected by the upload portal.
For JPEG exports, the browser conducts up to 15 binary-search iterations between quality 0.1 and 1.0 until the file size measures at or below 49 KB. If the compressed signature falls below 30 KB, the tool adds zero-byte padding inside an extra JPEG APP1 marker to bring the file to exactly 30 KB. This satisfies portals with a strict 30 KB floor without altering the visual appearance of your signature.
If a high-noise or very large image cannot be compressed under 49 KB even at quality 0.1, the code falls back to saving at quality 0.9. In that case, the resulting file will exceed 49 KB, and the status box will show “File size outside target range” instead of “Ready to use”. If you encounter this warning, crop closer to the signature strokes or reduce the resolution of your source file before uploading.
The canvas context fills with white (#ffffff) before drawing your image, which only affects transparent areas (such as in a transparent PNG). The tool does not bleach grey paper, clean up uneven phone shadows, or remove background wrinkles. Capture your signature on clean white paper under bright, uniform lighting without casting phone shadows over the page.
Frequently asked questions
What is 50x20 mm in pixels at 300 DPI resolution?
At 300 DPI print and scan resolution, 50×20 mm computes to approximately 590 pixels wide by 236 pixels high, representing a 2.5:1 aspect ratio.
Does UPSC specify a 50x20 mm signature format?
No. UPSC’s OTR FAQ gives 350×350 to 1000×1000 pixels and 20–300 KB for the signature. The 50×20 mm box appears in RRB’s CEN 06/2024, though RRB’s CEN 03/2025 uses a 35×20 mm box instead.
Can I sign in capital letters on a railway (RRB) application?
No. CEN 06/2024 requires running letters, not block letters, and CEN 03/2025 lists a signature in BLOCK or CAPITAL letters as a ground for rejection.
Does this tool guarantee my signature falls within 30 to 49 KB?
Yes, for normal signature images. The tool compresses to under 49 KB and automatically pads any output smaller than 30 KB up to the 30 KB minimum. Only very noisy or uncropped images that exceed 49 KB at quality 0.1 will show “File size outside target range”.
Does this tool remove shadows from mobile phone photos of signatures?
No. The white canvas layer only shows through transparent pixels. It does not erase shadows or whiten paper backgrounds on regular camera photos. Photograph your signature under direct, balanced light.
Why were the ends of my signature trimmed off?
The tool center-crops the input to a 2.5:1 ratio. If your signature is long or off-center, the edges will be cut off. Crop your photo manually so the signature is centered with clear margins before uploading.
Is my signature saved or transmitted to an external server?
No. The crop, the canvas drawing and the JPEG compression all happen on your own device, and the file is not sent to a server.