File preparation
PNG, JPG or SVG: best format for DTF
When to export raster, when to design vector and what to avoid in production.
6 min read
PNG: the standard almost everyone accepts
PNG at 300 DPI, actual size, with a clean alpha channel is the safest handoff for DTF suppliers and common RIPs. No lossy compression: every intermediate JPEG save degrades edges white ink cannot fix later. Export from the master document, not screenshots or rescaled social downloads.
Bit depth matters: use PNG-24 for full color and transparency already fixed or hardened per your soft-alpha guide. Avoid PNG-8 except simple few-color icons, because limited palettes band gradients and cause unexpected shifts on garment.
Embed color profile only if your supplier asks; many workflows prefer sRGB without embedded profile to avoid double conversion. Ask once and document the answer in your checklist. Consistency across orders beats experimenting every gang sheet.
Name files with version: Client_Design_v3_PRINT.png. If you send ZIP, confirm nobody opened and re-exported in other software inside the pack. An “almost same” PNG with different compression can make a whole batch look unlike the last one.
SVG and AI: scalable design, raster delivery
SVG is excellent while designing: sharp logos, editable type and fast color changes. DTF production almost always consumes raster at print size; vector becomes raster in the RIP or by you before the sheet. Do not send SVG expecting the supplier to “fix it” without fee or time.
In Illustrator, work in real units (cm or inches) and export PNG with saved settings. Outline type if you do not embed fonts. Objects with appearance effects must expand before export so what you see is what prints.
PDF can carry vector for shops that rasterize internally, but confirm they accept PDF and at what resolution they rasterize. A PDF with 72 DPI embedded images does not improve in print; embed images at 300 DPI at final size or link correctly.
Keep SVG/AI archived as source of truth and PNG_PRINT as the production contract. When the client asks a color change, edit vector and regenerate PNG in minutes without redesigning from a screenshot.
JPG: when yes and when never
JPG fits source photography without transparency: portrait, landscape, photo texture you will composite in Photoshop and export to PNG for DTF. It is not final print format if you need clean edges or alpha: compression creates artifacts around the subject.
If you receive a logo as JPG, assume damaged edges and a “almost” white background. Vectorize or redraw before promising quality. Exporting at high quality does not remove prior JPEG blocks; it only softens them slightly.
For web catalogs you can use light JPG; separate WEB and PRINT folders so rush jobs do not pick wrong files. One wrong click on the sheet costs a meter. Color space: convert photos to sRGB before compositing if your supplier prints in that space.
Avoid JPG → PNG → JPG chains. Each lossy hop accumulates grime visible in white and flat colors. One final PNG export from the master composite at maximum quality.
Color profiles and rich black
Ask whether your supplier prints direct RGB, converted CMYK or custom ICC. Designing in the wrong space shifts reds, oranges and greens on garment. Keep a test shirt with a color grid from your usual workflow to compare month to month.
DTF black is not offset “C100 M100 Y100 K100”: in many workflows black comes from the color channel plus white underneath. For large black areas, ask if plain black or black with some CMY reduces cracking; it depends on powder and fabric.
Neons and fluorescents on screen rarely match fabric; set expectations. If the client brings Pantone, work from approximate physical sample, not digital swatch only. Document “color approved on mockup, ±X variation on fabric”.
Disable “emulate print color” without the shop’s exact profile; it can make you design dull colors for no reason. Better calibrate from successful order history with the same supplier.
File size, DPI and common myths
An 80 MB PNG is not “better” if upscaled from 72 DPI: weight only reflects pixels, not real detail. The rule remains enough pixels at print size (effective 300 DPI in critical areas). Photos may tolerate slightly less on huge pieces viewed at distance.
Do not confuse document DPI with supplier printer DPI; they are different conversations. Your job ends at clean raster at agreed size. If the supplier asks 600 DPI for fine type, double resolution only after validating their RIP uses it.
Layered PSD/AI files do not replace PNG on self-serve gang sheet portals: upload PNG unless the site explicitly asks otherwise. Attach PSD in notes only when you pay pro prep.
ZIP without recompressing images inside. Use lossless PNG optimizers only if your supplier confirms alpha is untouched; when unsure, standard PNG from Photoshop Export As.
Supplier handoff and format mistakes
Prepare a short README on the order: qty, sizes, chest/back placement, file name per piece, white notes. Correct format mislabeled still prints on the wrong garment even when PNG is perfect.
If you use an online meter builder, verify it does not convert everything to JPG on upload. Some platforms compress hard; then negotiate Drive delivery with original PNGs and layout reference.
For international suppliers, confirm gang sheet cut-off timezone: “received before 10 am” may be your midnight. Format matters less than time if you miss the day’s run.
Archive PRINT exports with date and supplier. When a client claims “last time looked different”, you compare bytes and settings, not memory.
Right format, fewer reworks
Mastering PNG, vector source and JPG limits puts you in the 10% of clients suppliers prioritize: fewer tickets, less delay, better long-term pricing. Format is the first signal of professionalism.
Pair this guide with true resolution, hardened transparency and a pre-print checklist. Together they remove most “bad file” returns.
If you buy ready designs, demand PNG_PRINT with specs; if you design, automate export with saved actions so not one pixel drifts between orders.
At Limited Library you get a DTF design membership, tools like the meter builder and vectorizer, and Canva templates to sell before you print.
FAQ
Can I send PDF instead of PNG?
Only if your supplier confirms and you know their raster settings. For most shops, 300 DPI PNG at actual size is the surprise-free choice.
CMYK or RGB for DTF?
Depends on the shop’s RIP. Ask and design in the space they specify; do not convert blindly.
Does SVG scale without quality loss in DTF?
It scales in design, but printing uses raster at final size. Always validate the exported PNG, not only the vector.
Maximum file weight?
Varies by portal; if over limit, lossless PNG optimize or send a link. Prioritize clean alpha over aggressive compression.
Related guides
What resolution should a DTF design have?
Correct resolution avoids the pixel look after the first wash.
Read guide →How to prepare a design for DTF printing
Prepare professional files that cut reprints and speed up your gang sheet.
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