Astable oscillator
API · /timer555-api
555 Timer Calculator API
healthy
3,256 Subscribers
555-timer (NE555) astable and monostable design as an API, computed locally and deterministically. The astable endpoint designs the classic oscillator: from the two timing resistors R1 and R2 and the capacitor it returns the output frequency f = 1/(ln2·(R1+2R2)·C), the high and low times (T_high = ln2·(R1+R2)·C, T_low = ln2·R2·C), the period and the duty cycle (R1+R2)/(R1+2R2), or solves the capacitor for a target frequency. The monostable endpoint designs the one-shot timer, T = 1.1·R·C — the pulse width of a single output pulse — and solves for whichever of the resistance, capacitance or pulse width you leave out. The design endpoint works backwards: from a target frequency, a chosen capacitor and a duty cycle it computes the resistor values R1 and R2 you need (a standard 555 needs a duty above 50 %). Capacitors may be entered in farads, microfarads, nanofarads or picofarads. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics-hobbyist and maker tools, oscillator, blinker, PWM and timing-circuit design, and electronics education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is 555-timer design; for Ohm's law, reactance and RC time constants use an Ohm's-law API.
api.oanor.com/timer555-api
API health
healthy- Uptime
- 100.00%
- Server probes · 24h
- Avg latency
- 86 ms
- Server probes · 24h
- Subscribers
- 3,256
- active
- Total calls
- 32
- last 7 days
Pricing
Pick a tier — billed monthly, cancel anytime.
Free
Free
- 2,000 calls / month
- 2 requests / second
- Hard cap (429 above quota, no overage)
- Astable frequency + duty-cycle from R1/R2/C
- Monostable pulse-width from R/C
- NE555 standard formulas
- JSON request/response
Starter
€8.00 /month
- 25,000 calls / month
- 5 requests / second
- Hard cap (429 above quota, no overage)
- Astable + monostable design endpoints
- Reverse-solve R/C for a target frequency
- E12 standard-value component suggestions
- Deterministic, instant results
Pro
€22.00 /month
- 150,000 calls / month
- 15 requests / second
- Hard cap (429 above quota, no overage)
- High-throughput batch design calls
- E24 component snapping + tolerance bounds
- Min/max frequency range from part tolerances
- Priority support
Mega
€69.00 /month
- 768,000 calls / month
- 40 requests / second
- Hard cap (429 above quota, no overage)
- Bulk oscillator/timer design at scale
- Full E24 BOM + duty-cycle optimization
- Worst-case timing across temperature drift
- SLA-backed throughput for CAD/EDA tools
Built by
Related APIs
Other APIs with overlapping tags.
Voltage Divider API
Resistive voltage-divider circuit design as an API, computed locally and deterministically. The divide endpoint takes an input voltage and two resistors and returns the output voltage Vout = Vin·R2/(R1+R2), the current I = Vin/(R1+R2) that flows through the chain, and the power dissipated in each resistor and in total — a 12 V source with R1 = 1 kΩ and R2 = 2 kΩ gives 8 V at 4 mA. The loaded endpoint adds a load resistor across R2, computes the parallel combination R2′ = R2·RL/(R2+RL) and the loaded output Vout = Vin·R2′/(R1+R2′), and reports the droop in volts and percent against the unloaded value, the classic mistake when a divider feeds a real load. The resistor endpoint sizes the missing resistor for a target output — R2 = R1·Vout/(Vin−Vout) or R1 = R2·(Vin−Vout)/Vout — so you can pick parts for a reference or sensor-bias point. All quantities are volts, ohms, amps and watts. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics, embedded, hardware, sensor-interfacing and EE-education app developers, reference-voltage and bias-network tools, and maker software. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is the resistive divider; for a single Ohm’s-law relationship use an Ohm’s-law API and for RC/RL filters an RC-filter API.
api.oanor.com/voltagedivider-api
RC Filter API
First-order RC and RL passive-filter design as an API, computed locally and deterministically. The lowpass and highpass endpoints take a resistor and capacitor (RC) or a resistor and inductor (RL) and return the −3 dB cutoff frequency (fc = 1/(2πRC) for RC, R/(2πL) for RL), the time constant (τ = RC or L/R) and the angular cutoff; pass a frequency as well and they add the magnitude response as a linear gain and in decibels and the phase shift in degrees — a 1 kΩ / 1 µF low-pass has fc ≈ 159.15 Hz, and right at the cutoff the gain is −3.01 dB with −45° phase for a low-pass or +45° for a high-pass. The component endpoint solves the missing one of fc, R and C from the other two (fc = 1/(2πRC)), so you can size a resistor or capacitor for a target cutoff. All quantities are SI: ohms, farads, henries and hertz. Everything is computed locally and deterministically, so it is instant and private. Ideal for electronics, audio, embedded, signal-processing and EE-education app developers, filter-design and circuit-sizing tools, and maker software. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is first-order single-pole filter design; for full RLC impedance and resonance use an impedance API and for stored capacitor energy a capacitor API.
api.oanor.com/rcfilter-api
Chebyshev Filter API
Chebyshev Type I filter-design maths as an API, computed locally and deterministically. The order endpoint computes the minimum filter order to meet a specification, n = ⌈acosh(√((10^(As/10)−1)/(10^(Ap/10)−1))) / acosh(fs/fp)⌉, from the passband edge frequency and its ripple and the stopband edge and its required attenuation — a Chebyshev filter usually needs a lower order than a Butterworth for the same specification, trading a flat passband for equiripple. The response endpoint computes the equiripple magnitude response, |H| = 1/√(1 + ε²·Tₙ²(f/fc)) with the ripple factor ε = √(10^(Ap/10) − 1) and the Chebyshev polynomial Tₙ, in linear and decibel form — in the passband the magnitude ripples between 0 and −Ap dB and reaches exactly −Ap dB at the cutoff, then rolls off faster than a Butterworth. The ripple endpoint converts between the passband ripple in decibels and the ripple factor ε, with the passband maximum and minimum. Frequencies are in hertz, ripple and attenuation in decibels and the order a positive integer. Everything is computed locally and deterministically, so it is instant and private. Ideal for DSP, audio, RF, communications and instrumentation app developers, filter-design and selectivity tools, and signal-processing education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is the Chebyshev Type I filter; for the maximally-flat Butterworth use a Butterworth API.
api.oanor.com/chebyshev-api
Butterworth Filter API
Butterworth-filter design maths as an API, computed locally and deterministically. The order endpoint computes the minimum filter order needed to meet a specification — from the passband edge frequency and its allowed ripple and the stopband edge frequency and its required attenuation it returns the exact and rounded-up order, n = ⌈log10((10^(As/10)−1)/(10^(Ap/10)−1)) / (2·log10(fs/fp))⌉, where each extra order adds 20 dB per decade of roll-off. The response endpoint computes the maximally-flat magnitude response of an n-th order Butterworth filter at a frequency, |H| = 1/√(1 + (f/fc)^(2n)), in linear and decibel form with the attenuation and the asymptotic roll-off — the response is exactly −3.01 dB at the cutoff for any order. The poles endpoint gives the s-plane pole locations, equally spaced on a circle of radius ωc in the left half-plane at angles π·(2k+n−1)/(2n), all stable. Frequencies are in hertz (or any consistent unit), ripple and attenuation in decibels and the order a positive integer. Everything is computed locally and deterministically, so it is instant and private. Ideal for DSP, audio, RF, instrumentation and embedded app developers, anti-aliasing and filter-design tools, and signal-processing education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is the Butterworth filter; for a single-pole RC cutoff and resonance use a resonance API and for AC impedance an impedance API.
api.oanor.com/butterworth-api
Frequently asked questions
Quick answers about pricing, quotas, and integration.
How do I get an API key for 555 Timer Calculator API?
Sign up for free at oanor.com, generate an API key from the developer dashboard, and call 555 Timer Calculator API with the x-oanor-key header. No credit card needed for the free tier.
What's the rate limit for 555 Timer Calculator API?
Free tier allows 1 request per second. Paid plans scale up to 50 requests per second on the Mega tier. Hard limits return HTTP 429 above the quota — no surprise overage charges.
How much does 555 Timer Calculator API cost?
555 Timer Calculator API has a free tier with 100 calls / month. Paid plans start at €8.00 / month with higher quotas and faster rate limits.
Can I cancel my subscription anytime?
Yes. Plans are billed monthly and you can cancel anytime from your billing dashboard. No long-term contracts and no cancellation fee.
Is 555 Timer Calculator API GDPR-compliant?
All requests to 555 Timer Calculator API go through our EU-based gateway. Your upstream API key never leaves our server and no personal data is shared with the upstream provider beyond the request you send.
Pick an endpoint from the list on the left to see its details and try it.
Code snippets
Sign up to get an API key, then call any path under your slug.
curl https://api.oanor.com/timer555-api/SOME_PATH \
-H "x-oanor-key: oanor_test_..."const res = await fetch("https://api.oanor.com/timer555-api/SOME_PATH", {
headers: { "x-oanor-key": "oanor_test_..." }
});
const data = await res.json();$ch = curl_init("https://api.oanor.com/timer555-api/SOME_PATH");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-oanor-key: oanor_test_..."]);
$response = curl_exec($ch);import requests
r = requests.get(
"https://api.oanor.com/timer555-api/SOME_PATH",
headers={"x-oanor-key": "oanor_test_..."},
)
print(r.json())Ratings
Sign in to rate.
No reviews yet.
Discussion
Ask questions, share usage tips, get answers from the provider and other developers. Public — anyone can read.
Sign in to start a thread or reply.
Sign inNew thread
📌 Pinned
🔒 Locked
·
·
·
-
Provider answer
🔒 This thread is locked — no new replies.
-
·
- No threads yet — start the discussion.
Support
Private 1:1 support with the provider — billing questions, integration issues, account problems. Only you and the provider team can see these threads.
Sign in to open a support ticket.
Sign inOpen new ticket
Describe what you need help with. The provider team gets an email and replies on the ticket page.
-
·
Urgent - No tickets yet for this API.