ForHosting KIT
Free tools that work
right in your browser.
Calculators, converters, PDF, text, images and much more — each with its own page. Type your data and get the result right here, with no sign-up and without your data leaving your device. Need them in your own app? The same tools are available by API.
REST APILive
EmailLive
Webkit.forhosting.comLive
TelegramLive
iOS & AndroidBuilding
WhatsAppComing
7830tools
7432free in your browser
8languages
6channels
Find your tool
Search in your own words or filter by category.
🔬 ScienceFree
Angle of refraction calculator
Going from index 1 into glass of 1.5 at 30°, a ray refracts to 19.4712206345° and turns by 10.5287793655°.
H
Runs in your browser
🔬 ScienceFree
Angle of twist calculator
A 100 N·m torque on a steel shaft 1.5 m long and 0.02 m across twists it 0.120877171969 rad, almost 7°.
H
Runs in your browser
🔬 ScienceFree
Angular frequency calculator
50 Hz mains corresponds to an angular frequency of 314.159265359 rad/s, with a period of 0.02 s. Enter any positive frequency in hertz to get ω in radians per…
H
Runs in your browser
🔬 ScienceFree
Angular resolution calculator
A 200 mm telescope observing green light at 550 nm can separate two stars 0.692018 arcseconds apart, its diffraction limit.
H
Runs in your browser
🔬 ScienceFree
Aperture area calculator
A 200 mm telescope mirror has a collecting area of 31415.926536 mm², four times that of a 100 mm mirror.
H
Runs in your browser
🔬 ScienceFree
API gravity calculator
A crude with a specific gravity of 0.85 reads 34.970588235294 degrees on the American Petroleum Institute scale and is classed as light.
H
Runs in your browser
🔬 ScienceFree
Arrow speed calculator
A 50 lb bow drawn 28 inches can launch a 400-grain arrow at up to 362.38 ft/s, the theoretical ceiling with perfect efficiency.
H
Runs in your browser
🔬 ScienceFree
Attenuation in dB
Going from 100 W in to 1 W out is a loss of exactly 20 dB, and halving the power costs about 3 dB.
H
Runs in your browser
🔬 ScienceFree
Ballistic coefficient calculator
A body with twice the ballistic coefficient slows half as fast in the same air. Enter mass, drag coefficient and cross-sectional area to get that number, plus…
H
Runs in your browser
🔬 ScienceFree
Bank angle calculator
At 120 m/s on a 1,500 m radius, a level turn needs a bank of just under 45°. Enter airspeed and radius in coherent units and read the angle in degrees and…
H
Runs in your browser
🔬 ScienceFree
Barn-pole paradox calculator
A 20 m pole moving at 0.9 times light speed shrinks to under 9 m in the frame of a 10 m barn, so it fits.
H
Runs in your browser
🔬 ScienceFree
Belt length calculator
Pulleys of 200 and 100 mm with shafts 500 mm apart need 1,000 mm of straight belt plus two wrap arcs and a 5 mm correction.
H
Runs in your browser
🔬 ScienceFree
Bend allowance calculator
A 90° bend at 5 mm inside radius in 2 mm sheet, with a K-factor of 0.33, takes just under 9 mm of arc.
H
Runs in your browser
🔬 ScienceFree
Binoculars range calculator
Under ideal conditions, 10x42 binoculars still resolve a 1.8 m person at more than 60 km, because the eye's limit, not the lens, sets the bound.
H
Runs in your browser
🔬 ScienceFree
Biot number calculator
With h of 25, a characteristic length of 0.05 m and k of 15, the Biot number is 0.083. Get that dimensionless number plus a check of whether a…
H
Runs in your browser
💰 Finance & moneyFree
Rent vs buy cost calculator
Put renting and owning a home side by side over the same period: 1,800 in rent against 2,350 a month to own comes to 216,000 versus 282,000 over 10 years, so…
B
Runs in your browser
⚙️ Developer UtilitiesFree
Build a Content-Security-Policy header from allowed sources
Four rows, from default-src with 'self' to upgrade-insecure-requests on its own, become one policy line joined by semicolons, in your order.
R
Runs in your browser
⚙️ Developer UtilitiesFree
Convert Unix permissions between symbolic and octal
rwxr-xr-- converts to 754, and 754 converts back to rwxr-xr--, because read counts 4, write 2 and execute 1 for each audience.
B
Runs in your browser
⚙️ Developer UtilitiesFree
Seeded memorable passphrase generator
With 6 words and a hyphen, the same private seed always returns parade-orange-globe-marsh-birch-earth, so the phrase can be rebuilt instead of stored.
F
Runs in your browser
📈 SEOFree
Check image alt text coverage
Paste your image list and see what share has useful alt text: in the example, 2 of 5 images pass, so coverage is 40%.
K
Runs in your browser
📈 SEOFree
Anchor Text Diversity Checker
Enter your target keyword and the anchors pointing to one page: for email marketing software, six sample anchors split into 1 exact match, 2 partial, 2 generic…
R
Runs in your browser
📈 SEOFree
Canonical tag conflict checker
Enter the page address and the address in its canonical tag and see at once whether they match: in the example, a product page ending in #details matches…
R
Runs in your browser
📈 SEOFree
Duplicate content checker
Paste two texts and see how much of their wording they share: the two sample product sentences score 46.67%, with 7 of 15 three-word phrases in common, below…
B
Runs in your browser
📈 SEOFree
Check heading structure hierarchy
List your headings in page order and see whether the hierarchy holds: h1, h2, h3, h2, h3 passes, while going from h2 straight to h4 is reported as a missing h3…
R
Runs in your browser
📈 SEOFree
Check hreflang tag consistency and reciprocal links
Find the page that breaks a hreflang group: enter the declarations from each version and get the precise links each one lacks.
R
Runs in your browser
📈 SEOFree
Check image filename SEO
Know before upload whether an image name helps: red-running-shoes-side-view.jpg passes, while untitled.webp is flagged as generic.
K
Runs in your browser
📈 SEOFree
SEO keyword density report
Measure one keyword against your own limit: technical SEO used three times in 23 words fills 26.09 % of the text and is flagged above a 20 % threshold.
B
Runs in your browser
📈 SEOFree
Meta description length checker
Know at once whether a meta description fits: a 143-character draft lands inside the recommended 120 to 160 range.
M
Runs in your browser
📈 SEOFree
Pagination rel prev and next tag checker
Confirm a paginated series links up both ways: three pages with four correctly aimed links pass with zero issues.
K
Runs in your browser
📈 SEOFree
SEO content readability grade
Check whether a page suits its readers: two short sentences of 11 words and 17 syllables score grade 4.79, well under a target of 8, so they pass.
F
Runs in your browser
📈 SEOFree
Robots meta tag checker
Find out what a robots meta tag really says: noindex, follow, max-snippet:120, max-image-preview:large keeps the page out of results, lets crawlers follow links…
M
Runs in your browser
📈 SEOFree
Schema.org type fields lookup
See which properties a page type needs before you write any markup: Product needs name and image, and adds description, sku, brand, offers, aggregateRating and…
B
Runs in your browser
📈 SEOFree
SERP snippet preview
Preview a search result before you publish: a title cut at 60 characters, a URL at 75 and a description at 160, each ending in an ellipsis when it runs over.
F
Runs in your browser
📈 SEOFree
Check URL slug SEO quality
Review a slug before you publish: best-running-shoes-women checked against best running shoes for women scores 100, with all four meaningful terms matched and…
M
Runs in your browser
📈 SEOFree
Title click-worthiness score
See why a headline scores as it does: 10 Proven Ways to Boost Your SEO Today? earns 91, with 30 points for its number, 36 for three power words and 25 for the…
M
Runs in your browser
📈 SEOFree
Title vs meta description overlap checker
Check whether a description echoes its title or adds to it: Affordable Solar Panels for Homes shares four words with its description, an overlap of one third…
F
Runs in your browser
📈 SEOFree
SEO title length checker
Check a title by width, not just characters: A Practical Guide to Writing Better SEO Titles, at 46 characters, takes about 297 of the 580 pixels, leaving 283.
F
Runs in your browser
📈 SEOFree
Compare word count to benchmark
Enter a page's total word count and its content type to see whether it is under, within or over the benchmark: a 1350-word blog post sits inside the 1000 to…
B
Runs in your browser
🧭 Travel & geographyFree
Daily trip budget calculator
A 2400 budget for eight days gives 300 a day; with 50 % lodging, 30 % food and 20 % activities, that is 150, 90 and 60 per day.
F
Runs in your browser
🎬 VideoFree
Compute video aspect ratio crop
Turn a 1920×1080 landscape frame into 9:16 vertical video with a crop that starts 656.25 pixels from the left and keeps a 607.5 by 1080 rectangle, the largest…
F
Runs in your browser
🎬 VideoFree
Video bitrate calculator for a target file size
A 600-second video that must stay under 100 MB needs about 1,267 kbps for video and audio together, once a 5 % safety margin trims the theoretical maximum.
B
Runs in your browser
🎬 VideoFree
Video container and codec compatibility checker
MP4 with H.264 comes back as broad support, the safest choice across major browsers, iOS and Android, while an unusual pair such as VP9 in MOV is flagged before…
B
Runs in your browser
🎬 VideoFree
Video frame rate conversion calculator
Moving 240 frames from 24 fps to 30 fps needs 60 duplicated frames, 300 in all, to keep the full 10 seconds; playing the original 240 at 30 fps instead lasts…
R
Runs in your browser
🎬 VideoFree
Freeze Frame Duration Calculator
Hold a frame for 4.25 seconds at the 32.5-second mark of a 90-second video and the finished cut runs 94.25 seconds.
K
Runs in your browser
🎬 VideoFree
GIF frame count calculator
A 12.5-second clip at 10 fps becomes a GIF of 125 frames, against 313 in the 25 fps source, so the animation carries roughly two-fifths of the original frame…
K
Runs in your browser
🎬 VideoFree
Check video loop seam compatibility from frame colors
Two end frames whose red, green and blue averages differ by just 3 points overall, with brightness 0.5 apart, score 99.4174 out of 100 and pass the default 90…
R
Runs in your browser
🎬 VideoFree
Audio video sync offset calculator
When the sound arrives 180 milliseconds before the picture, delay the audio by 180 milliseconds and leave the video untouched.
R
Runs in your browser
🎬 VideoFree
Estimate video render time from duration and encoder speed
A two-minute program at 30 frames per second holds 3,600 frames, so an encoder sustaining 60 frames per second needs about one minute, twice as fast as…
B
Runs in your browser
🎬 VideoFree
Video resolution scale calculator
Pick a delivery label and see the exact frame size: 1920 by 1080 converted to 720p becomes 1280 by 720, a factor of 0.666667, with a clear warning whenever the…
K
Runs in your browser
🎬 VideoFree
Video speed change duration calculator
A 300-second video played at 1.25 speed lasts 240 seconds, exactly four minutes, and its untreated audio would rise almost four semitones.
F
Runs in your browser
🎬 VideoFree
Generate a Storyboard Shot List Template
Describe a cyclist crossing an empty town square at dawn, ask for five shots and get a 25-second plan, from an establishing wide shot to a detail insert, built…
F
Runs in your browser
🎬 VideoFree
Convert SRT subtitles to WebVTT online
Turn an SRT subtitle file into WebVTT that web players accept: 00:00:01,250 becomes 00:00:01.250, the WEBVTT header is added and multiline captions stay intact…
R
Runs in your browser
🎬 VideoFree
Compute video thumbnail timestamps evenly
A 120-second video split into five previews gets evenly spaced frames that start at second 1, stop one second before the end and put the middle one at 60, away…
K
Runs in your browser
🎬 VideoFree
Trim video by timestamp
Check a cut before you make it: in a video of 01:42:30, a clip from 00:12:15.5 to 00:14:45.75 is valid and lasts 150.25 seconds, or 00:02:30.25.
B
Runs in your browser
🎬 VideoFree
Video watermark position calculator
Place a 240 by 120 logo in the bottom-right corner of a 1920 by 1080 frame with a 32-pixel margin and get its top-left point, x 1648 and y 928, checked to fit…
B
Runs in your browser
🎬 VideoFree
B-Roll to A-Roll Ratio Checker for Video Edits
See the balance of your cut in one number: 180 seconds of B-roll in a 600-second interview is 30 %, inside the usual 20 to 35 % range, so you can talk about…
K
Runs in your browser
🎬 VideoFree
Drop-frame vs non-drop timecode checker and frame calculator
Turn a timecode into an exact frame position: at 29.97 fps, 01:00:00;00 in drop-frame is frame 107892, after 108 skipped labels, or 3599.9964 seconds of real…
F
Runs in your browser
🎬 VideoFree
Video export preset lookup by platform
Get matching export settings for where the video is going: for YouTube the preset is H.264 at 3840x2160, 60 fps and 53 Mbps, with vertical formats for Instagram…
R
Runs in your browser
🎬 VideoFree
Calculate total render queue time and completion time
Three clips of 95, 430 and 35 seconds make a 560-second queue (9 min 20 s): started at 14:20 UTC, it finishes at 14:29:20 UTC.
B
Runs in your browser
🕸️ Web Scraping & MonitoringFree
Resolve a relative URL against a base URL
Turn a relative link into the exact address a browser would use: from the page start.html in docs/guides, the link ../images/logo.svg lands in docs/images on…
R
Runs in your browser
No capabilities match your search.
How it works
1
Get your key
Create an account with your email and add balance when you need it. No subscription, no sales call.
2
Call the endpoint
One authenticated POST. The API returns a task_id immediately — copy-paste snippets in five languages on every page.
3
Collect the result
Receive a signed webhook the moment it's ready, or fetch a signed link. A failed task is never charged.
Pay only for what you use
No subscription. Free tools run in your browser; paid tasks draw from your balance, which never expires.
Free tools
$0.00
On-device utilities — hash, QR, JSON, Text→PDF and more — run in your browser. No account, no limits.
Pay-as-you-go
Per task
$0.002+
The full API — 7800+ capabilities — billed only for what you run, from $0.002 per call. No monthly fee.
Balance
$10.00+
Top up your balance and spend it across web, API and the app. It never expires.